Ensure that a fullscreen RenderWidgetHostViewAura instance does not restore...

Ensure that a fullscreen RenderWidgetHostViewAura instance does not restore itself on Windows when we switch away to a different
monitor.

We have code in RenderWidgetHostViewAura::OnWindowFocused to handle this case. It does this by comparing the display ids of
the window being activated and the one losing activation. However in desktop Chrome we could lose activation to a non Aura Window.

We handle this case on Windows by getting the cursor position and the display near that and comparing that with the display of the
window losing activation.

Fixes bug https://code.google.com/p/chromium/issues/detail?id=317532

BUG=317532
R=jam@chromium.org, jam

Review URL: https://codereview.chromium.org/100683002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@238441 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/render_widget_host_view_aura.cc

@@ -2979,6 +2979,17 @@ void RenderWidgetHostViewAura::OnWindowFocused(aura::Window* gained_focus,
         (screen->GetDisplayNearestWindow(window_).id() !=
          screen->GetDisplayNearestWindow(gained_focus).id());
     if (is_fullscreen_ && !in_shutdown_ && !focusing_other_display) {
+#if defined(OS_WIN)
+      // On Windows, if we are switching to a non Aura Window on a different
+      // screen we should not close the fullscreen window.
+      if (!gained_focus) {
+        POINT point = {0};
+        ::GetCursorPos(&point);
+        if (screen->GetDisplayNearestWindow(window_).id() !=
+            screen->GetDisplayNearestPoint(gfx::Point(point)).id())
+          return;
+      }
+#endif
       in_shutdown_ = true;
       host_->Shutdown();
     }