Merge lp:~3v1n0/unity/blurring-crash-fix into lp:unity

[Marco Trevisan (Treviño)]

CairoBaseWindow: don't try to compute the blur of an invalid texture

Nux isn't smart enough to protect us.

As per https://errors.ubuntu.com/problem/23eed577b86c959a28589b8bb1a3bc6ee15b8694 bkg_texture is null, which leads to this error.

[Andrea Azzarone (azzar1)]

LGTM.

review: Approve

=== modified file 'launcher/CairoBaseWindow.cpp'
--- launcher/CairoBaseWindow.cpp	2016-07-04 12:45:06 +0000
+++ launcher/CairoBaseWindow.cpp	2018-02-21 14:35:25 +0000
@@ -110,8 +110,14 @@
 
     nux::ObjectPtr <nux::IOpenGLBaseTexture> bkg_texture = gfxContext.CreateTextureFromBackBuffer(base.x, base.y, base.width, base.height);
 
-    nux::TexCoordXForm texxform_bkg;
-    bg_blur_texture_ = gfxContext.QRP_GetBlurTexture(0, 0, base.width, base.height, bkg_texture, texxform_bkg, nux::color::White, 1.0f, 3);
+    if (bkg_texture.IsValid())
+    {
+      nux::TexCoordXForm texxform_bkg;
+      bg_blur_texture_ = gfxContext.QRP_GetBlurTexture(0, 0, base.width, base.height, bkg_texture, texxform_bkg, nux::color::White, 1.0f, 3);
+
+      if (bg_blur_texture_)
+        compute_blur_bkg_ = false;
+    }
 
     if (current_fbo.IsValid())
     {
@@ -124,7 +130,6 @@
       gfxContext.Push2DWindow(gfxContext.GetWindowWidth(), gfxContext.GetWindowHeight());
       gfxContext.ApplyClippingRectangle();
     }
-    compute_blur_bkg_ = false;
   }
 
   // the elements position inside the window are referenced to top-left window