I proposed using Valgrind during testing for easier triaging:
https://code.launchpad.net/~rbalint/unity-greeter/test-with-valgrind/+merge/321056

Is shows the following issues:

/Simple Navigation: ==5515== Conditional jump or move depends on uninitialised value(s)
==5515==    at 0xBEA881E: ??? (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.34.0)
==5515==    by 0xBE8C67A: ??? (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.34.0)
==5515==    by 0xBE47F40: pixman_image_composite32 (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.34.0)
==5515==    by 0x6E4569A: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E8A999: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E7CC3D: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E7D6B2: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E7E1D9: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E38ACE: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E4A291: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E81715: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E40E6E: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E3A438: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x6E333D4: cairo_stroke (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.8)
==5515==    by 0x1DF96905: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF92D21: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF88CBA: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF89F5F: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF8A421: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF8AD37: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF974A2: rsvg_handle_render_cairo_sub (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF97997: rsvg_handle_get_pixbuf_sub (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DD60E35: ??? (in /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so)
==5515==    by 0x60E7A62: gdk_pixbuf_loader_close (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.3600.5)
==5515==    by 0x60E3A4A: ??? (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.3600.5)
==5515==    by 0x60E533C: gdk_pixbuf_new_from_stream_at_scale (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.3600.5)
==5515==    by 0x533BAF9: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x533ED27: gtk_icon_info_load_icon (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5338189: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x53388F6: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5338A23: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5338C17: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x534C27C: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x534C9D2: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x526F4E2: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x51F07E0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x51F082A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5261CC0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5262682: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5261CC0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5262682: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413719: gtk_widget_get_preferred_height (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5318567: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5414003: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413719: gtk_widget_get_preferred_height (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54D8651: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5414003: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5414566: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54DA411: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54DAE5D: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x66A0E53: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BB57C: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BBC6E: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x54DCF72: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x66A0C24: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66B260B: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BB88B: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BBC6E: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x54C8FA1: gtk_widget_show (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x114413: test_setup (test.vala:11)
==5515==    by 0x1155A8: test_simple_navigation (test.vala:142)
==5515==    by 0x6954BB0: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954F8D: g_test_run_suite (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954FB0: g_test_run (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x118681: test_main (test.vala:802)
==5515==    by 0x766E3F0: (below main) (libc-start.c:291)
==5515== 
==5515== Conditional jump or move depends on uninitialised value(s)
==5515==    at 0x1DF96DA5: ??? (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DF979AB: rsvg_handle_get_pixbuf_sub (in /usr/lib/x86_64-linux-gnu/librsvg-2.so.2.40.16)
==5515==    by 0x1DD60E35: ??? (in /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-svg.so)
==5515==    by 0x60E7A62: gdk_pixbuf_loader_close (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.3600.5)
==5515==    by 0x60E3A4A: ??? (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.3600.5)
==5515==    by 0x60E533C: gdk_pixbuf_new_from_stream_at_scale (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.3600.5)
==5515==    by 0x533BAF9: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x533ED27: gtk_icon_info_load_icon (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5338189: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x53388F6: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5338A23: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5338C17: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x534C27C: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x534C9D2: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x526F4E2: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x51F07E0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x51F082A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5261CC0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5262682: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5261CC0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B02: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B6D50: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5262682: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413F4A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413719: gtk_widget_get_preferred_height (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5318567: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5414003: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5413719: gtk_widget_get_preferred_height (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54D8651: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5414003: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54141DE: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54144A5: gtk_widget_get_preferred_height_and_baseline_for_width (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5414566: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54DA411: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54DAE5D: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x66A0E53: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BB57C: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BBC6E: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x54DCF72: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x66A0C24: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66B260B: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BB88B: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BBC6E: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x54C8FA1: gtk_widget_show (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x114413: test_setup (test.vala:11)
==5515==    by 0x1155A8: test_simple_navigation (test.vala:142)
==5515==    by 0x6954BB0: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954F8D: g_test_run_suite (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954FB0: g_test_run (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x118681: test_main (test.vala:802)
==5515==    by 0x766E3F0: (below main) (libc-start.c:291)
==5515== 
OK
/Remote Login: ==5515== Invalid read of size 8
==5515==    at 0x54C166A: gtk_widget_translate_coordinates (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x13D7EE: prompt_box_real_draw_full_alpha (prompt-box.vala:597)
==5515==    by 0x139193: fadable_box_real_draw (fadable-box.vala:41)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x12A1B9: greeter_list_real_draw (greeter-list.vala:746)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5318390: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x525FD63: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B7C: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B79A7: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52627A0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x525FD63: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B7C: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B79A7: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52627A0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5318390: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54D8B90: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54D3C67: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5372039: gtk_main_do_event (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x4E73824: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E83EB7: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E850C5: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E852C3: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x66A0C24: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66B2C31: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BB88B: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BBC6E: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x4E7CEF8: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E680F7: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x692ECA2: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x692E229: g_main_context_dispatch (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x692E5DF: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x692E68B: g_main_context_iteration (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x5371274: gtk_main_iteration (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x114DF4: test_process_events (test.vala:29)
==5515==    by 0x114DF4: test_wait_for_scrolling_end (test.vala:36)
==5515==    by 0x1150FE: test_scroll_to_remote_login (test.vala:103)
==5515==    by 0x115847: test_remote_login (test.vala:175)
==5515==    by 0x6954BB0: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954F8D: g_test_run_suite (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954FB0: g_test_run (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x118681: test_main (test.vala:802)
==5515==    by 0x766E3F0: (below main) (libc-start.c:291)
==5515==  Address 0x0 is not stack'd, malloc'd or (recently) free'd
==5515== 
==5515== 
==5515== Process terminating with default action of signal 11 (SIGSEGV)
==5515==  Access not within mapped region at address 0x0
==5515==    at 0x54C166A: gtk_widget_translate_coordinates (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x13D7EE: prompt_box_real_draw_full_alpha (prompt-box.vala:597)
==5515==    by 0x139193: fadable_box_real_draw (fadable-box.vala:41)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x12A1B9: greeter_list_real_draw (greeter-list.vala:746)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5318390: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x525FD63: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B7C: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B79A7: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52627A0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x525FD63: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B2B7C: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52B79A7: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52627A0: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5318390: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADB3F: gtk_container_propagate_draw (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x52ADC21: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54D8B90: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54CA92A: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x54D3C67: ??? (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x5372039: gtk_main_do_event (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x4E73824: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E83EB7: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E850C5: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E852C3: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x66A0C24: g_closure_invoke (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66B2C31: ??? (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BB88B: g_signal_emit_valist (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x66BBC6E: g_signal_emit (in /usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0.5200.0)
==5515==    by 0x4E7CEF8: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x4E680F7: ??? (in /usr/lib/x86_64-linux-gnu/libgdk-3.so.0.2200.11)
==5515==    by 0x692ECA2: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x692E229: g_main_context_dispatch (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x692E5DF: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x692E68B: g_main_context_iteration (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x5371274: gtk_main_iteration (in /usr/lib/x86_64-linux-gnu/libgtk-3.so.0.2200.11)
==5515==    by 0x114DF4: test_process_events (test.vala:29)
==5515==    by 0x114DF4: test_wait_for_scrolling_end (test.vala:36)
==5515==    by 0x1150FE: test_scroll_to_remote_login (test.vala:103)
==5515==    by 0x115847: test_remote_login (test.vala:175)
==5515==    by 0x6954BB0: ??? (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954F8D: g_test_run_suite (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x6954FB0: g_test_run (in /lib/x86_64-linux-gnu/libglib-2.0.so.0.5200.0)
==5515==    by 0x118681: test_main (test.vala:802)
==5515==    by 0x766E3F0: (below main) (libc-start.c:291)
==5515==  If you believe this happened as a result of a stack
==5515==  overflow in your program's main thread (unlikely but
==5515==  possible), you can try to increase the size of the
==5515==  main thread stack using the --main-stacksize= flag.
==5515==  The main thread stack size used in this run was 8388608.
==5515== 
==5515== HEAP SUMMARY:
==5515==     in use at exit: 11,247,511 bytes in 124,447 blocks
==5515==   total heap usage: 628,751 allocs, 504,304 frees, 60,768,034 bytes allocated
==5515== 
==5515== LEAK SUMMARY:
==5515==    definitely lost: 13,824 bytes in 21 blocks
==5515==    indirectly lost: 53,617 bytes in 2,149 blocks
==5515==      possibly lost: 19,305 bytes in 252 blocks
==5515==    still reachable: 8,680,333 bytes in 105,507 blocks
==5515==                       of which reachable via heuristic:
==5515==                         length64           : 7,192 bytes in 109 blocks
==5515==                         newarray           : 2,128 bytes in 53 blocks
==5515==         suppressed: 0 bytes in 0 blocks
==5515== Rerun with --leak-check=full to see details of leaked memory
==5515== 
==5515== For counts of detected and suppressed errors, rerun with: -v
==5515== Use --track-origins=yes to see where uninitialised values come from
==5515== ERROR SUMMARY: 14 errors from 3 contexts (suppressed: 0 from 0)
Segmentation fault
==5553== Memcheck, a memory error detector
==5553== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==5553== Using Valgrind-3.12.0 and LibVEX; rerun with -h for copyright info
==5553== Command: /bin/rm -r /tmp/xvfb-run.saVrKh
==5553== 
...