DialogClientView: Handle nested close requests gracefully.

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 3cd043e2eb325ade6518cbbba973ce97210df3ad..f3638cd6d56e20a2e11ce6083e311dd377c5a445 100644
--- a/ui/views/window/dialog_client_view.cc
+++ b/ui/views/window/dialog_client_view.cc
@@ -87,19 +87,11 @@ DialogClientView::DialogClientView(Widget* owner, View* contents_view)
 DialogClientView::~DialogClientView() {}
 
 void DialogClientView::AcceptWindow() {
-  // Only notify the delegate once. See |delegate_allowed_close_|'s comment.
-  if (!delegate_allowed_close_ && GetDialogDelegate()->Accept()) {
-    delegate_allowed_close_ = true;
-    GetWidget()->Close();
-  }
+  CloseWithDelegateMethod(&DialogDelegate::Accept, true);
 }
 
 void DialogClientView::CancelWindow() {
-  // Only notify the delegate once. See |delegate_allowed_close_|'s comment.
-  if (!delegate_allowed_close_ && GetDialogDelegate()->Cancel()) {
-    delegate_allowed_close_ = true;
-    GetWidget()->Close();
-  }
+  CloseWithDelegateMethod(&DialogDelegate::Cancel, true);
 }
 
 void DialogClientView::UpdateDialogButtons() {
@@ -111,10 +103,24 @@ void DialogClientView::UpdateDialogButtons() {
 // DialogClientView, ClientView overrides:
 
 bool DialogClientView::CanClose() {
+  if (delegate_allowed_close_) {
+    DCHECK(!asking_delegate_whether_to_close_);
+    return true;
+  }
+
+  // The delegate may perform an action that causes the Widget to lose focus and
+  // (for some bubbles) attempt to close again. Widget::Close() has protection
+  // against multiple calls to Widget::Close(), but that method is above
+  // CanClose() in the stack: CanClose() has not yet told the first
+  // Widget::Close() whether it may proceed, so that protection can't be used.
+  // Detect this situation and always return false from the nested call to
+  // CanClose() so that Widget::Close() bails out early.
+  if (asking_delegate_whether_to_close_)
+    return false;
+
   // If the dialog is closing but no Accept or Cancel action has been performed
   // before, it's a Close action.
-  if (!delegate_allowed_close_)
-    delegate_allowed_close_ = GetDialogDelegate()->Close();
+  CloseWithDelegateMethod(&DialogDelegate::Close, false);
   return delegate_allowed_close_;
 }
 
@@ -419,4 +425,20 @@ void DialogClientView::SetupViews() {
     extra_view_->SetGroup(kButtonGroup);
 }
 
+void DialogClientView::CloseWithDelegateMethod(bool (DialogDelegate::*method)(),
+                                               bool close) {
+  DCHECK(!asking_delegate_whether_to_close_);
+
+  // Only notify the delegate once. See |delegate_allowed_close_|'s comment.
+  if (delegate_allowed_close_)
+    return;
+
+  {
+    base::AutoReset<bool> auto_reset(&asking_delegate_whether_to_close_, true);
+    delegate_allowed_close_ = (GetDialogDelegate()->*method)();
+  }
+  if (close && delegate_allowed_close_)
+    GetWidget()->Close();
+}
+
 }  // namespace views