Merge lp:~brandontschaefer/unity/alt+tab-focus-fix-6.0 into lp:unity/6.0

[Brandon Schaefer]

Fixes alt+tab losing focus when alt+tabing to quickly due to ubus being to slow to send a message.

When alt+tabing quick enough and sometimes it would lose focus. This was caused by ubus sometimes sending the UBUS_SWITCHER_START message after the switcher has shown...which focuses the switcher window...but since the switcher window was closed it stole the focus. Now it checks if the switcher is visible BEFORE focusing the input to the window.

There would be no reasonable/consistent way to test this...as it was a very hard problem to reproduce to begin with.

[Marco Trevisan (Treviño) (3v1n0)]

Good for me, waiting for the manual test before globally approving.

review: Approve

=== modified file 'manual-tests/Switcher.txt'
--- manual-tests/Switcher.txt	2012-08-21 22:09:19 +0000
+++ manual-tests/Switcher.txt	2012-09-26 18:08:19 +0000
@@ -103,3 +103,18 @@
 
 Expected Result:
   The assertions from above hold.
+
+Alt+Tab doesn't lose window focus
+---------------------------------
+This tests ensures that a racing condition is not possible anymore when alt+tabing.
+
+Setup:
+#. Have 2 windows of different types open. (gedit, nautilus)
+
+Actions:
+  #. Press quicky Alt+Tab. (so that the switcher window is not shown)
+  #. Repeat 10 times.
+
+Expected Results:
+  No window loses focuses at all. The panel should alway show the title of the
+  window.

=== modified file 'plugins/unityshell/src/unityshell.cpp'
--- plugins/unityshell/src/unityshell.cpp	2012-09-24 19:39:00 +0000
+++ plugins/unityshell/src/unityshell.cpp	2012-09-26 18:08:19 +0000
@@ -2086,7 +2086,8 @@
 
 void UnityScreen::OnSwitcherStart(GVariant* data)
 {
-  SaveInputThenFocus(switcher_controller_->GetSwitcherInputWindowId());
+  if (switcher_controller_->Visible())
+    SaveInputThenFocus(switcher_controller_->GetSwitcherInputWindowId());
 }
 
 void UnityScreen::OnSwitcherEnd(GVariant* data)