Added ignored_by_shelf bit to overview mode selection widget.

This change enables the selection widget to pass under the shelf without
activating it.

BUG=367766
TEST=none

Review URL: https://codereview.chromium.org/347813002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@278479 0039d316-1c4b-4281-b951-d872f2087c98

ash/wm/overview/window_grid.cc

@@ -358,6 +358,10 @@ void WindowGrid::InitSelectionWidget(WindowSelector::Direction direction) {
   // Disable the "bounce in" animation when showing the window.
   ::wm::SetWindowVisibilityAnimationTransition(
       selection_widget_->GetNativeWindow(), ::wm::ANIMATE_NONE);
+  // The selection widget should not activate the shelf when passing under it.
+  ash::wm::GetWindowState(selection_widget_->GetNativeWindow())->
+      set_ignored_by_shelf(true);
+
   views::View* content_view = new views::View;
   content_view->set_background(
       views::Background::CreateSolidBackground(kWindowOverviewSelectionColor));