Ensure app install is aborted when the install dialog is closed

ui/views/window/dialog_client_view.cc

Index: ui/views/window/dialog_client_view.cc
diff --git a/ui/views/window/dialog_client_view.cc b/ui/views/window/dialog_client_view.cc
index 17f71860057e63e8f736c39af8747044df309b31..e46586e442f4823efa3d32a187aa54b02916c0b6 100644
--- a/ui/views/window/dialog_client_view.cc
+++ b/ui/views/window/dialog_client_view.cc
@@ -139,6 +139,11 @@ bool DialogClientView::CanClose() {
   return false;
 }
 
+void DialogClientView::WidgetClosing() {
+  if (!notified_delegate_)

[tapted, 2014/09/08 07:42:21]

do you need `notified_delegate_ = true` here, and in DialogClientView::Close(),
below?

[tmdiep, 2014/09/08 08:26:08]

DialogClientView::Close() is called by AcceptWindow() and CancelWindow(), where
notified_delegate_ is set to true.

I went back and forth between whether to set the flag to true here.
The comment for notified_delegate_ in the header file says: "True if we've
notified the delegate the window is closing and the delegate allowed the close."
In this case the delegate did not allow the close, but the window is closing, so
I opted for this to ensure this flow remains unchanged:
When there is an accept, the order of execution is line 71 -> 429 -> 129
(returns at 130) -> 143 -> 430. 

[tapted, 2014/09/08 09:28:56]

sg - so long as Close() is private/non-virtual I think it makes sense

+    GetDialogDelegate()->OnClosed();
+}
+
 DialogClientView* DialogClientView::AsDialogClientView() {
   return this;
 }