Speculative fix for sticky keys overlay crash.

ash/sticky_keys/sticky_keys_overlay.cc

Index: ash/sticky_keys/sticky_keys_overlay.cc
diff --git a/ash/sticky_keys/sticky_keys_overlay.cc b/ash/sticky_keys/sticky_keys_overlay.cc
index 0766ba25ad2e7cdda2ac5ed875254de6622073e0..464d9f684567166abb0b56576568fad8a1cb3289 100644
--- a/ash/sticky_keys/sticky_keys_overlay.cc
+++ b/ash/sticky_keys/sticky_keys_overlay.cc
@@ -109,6 +109,7 @@ class StickyKeysOverlayView : public views::WidgetDelegateView {
 
   // views::WidgetDelegateView overrides:
   void OnPaint(gfx::Canvas* canvas) override;
+  void DeleteDelegate() override;
 
   void SetKeyState(ui::EventFlags modifier, StickyKeyState state);
 
@@ -166,6 +167,13 @@ void StickyKeysOverlayView::OnPaint(gfx::Canvas* canvas) {
   views::WidgetDelegateView::OnPaint(canvas);
 }
 
+void StickyKeysOverlayView::DeleteDelegate() {
+  // The ownership of a WidgetDelegateView is kind of tricky. It has the
+  // lifetime semantics of both a View and a WidgetDelegate. We should just rely
+  // on the Views semantics and do nothing here. This object will be deleted
+  // when the parent widget is deleted.
+}
+
 void StickyKeysOverlayView::SetKeyState(ui::EventFlags modifier,
                                         StickyKeyState state) {
   ModifierLabelMap::iterator it = modifier_label_map_.find(modifier);
@@ -279,6 +287,10 @@ StickyKeyState StickyKeysOverlay::GetModifierKeyState(
   return overlay_view_->GetKeyState(modifier);
 }
 
+views::Widget* StickyKeysOverlay::GetWidgetForTesting() {
+  return overlay_widget_.get();
+}
+
 gfx::Rect StickyKeysOverlay::CalculateOverlayBounds() {
   int x = is_visible_ ? kHorizontalOverlayOffset : -widget_size_.width();
   return gfx::Rect(gfx::Point(x, kVerticalOverlayOffset), widget_size_);