Use the default dispatcher where possible for nested message loops.

chrome/browser/ui/views/simple_message_box_views.cc

Index: chrome/browser/ui/views/simple_message_box_views.cc
diff --git a/chrome/browser/ui/views/simple_message_box_views.cc b/chrome/browser/ui/views/simple_message_box_views.cc
index 8deeebc76fac75a1d1cf8f6a64aaa267f072d795..c427d6b89bb695822346f26a709d2cb78d38be87 100644
--- a/chrome/browser/ui/views/simple_message_box_views.cc
+++ b/chrome/browser/ui/views/simple_message_box_views.cc
@@ -19,6 +19,7 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/views/controls/message_box_view.h"
+#include "ui/views/corewm/window_util.h"
 #include "ui/views/widget/widget.h"
 #include "ui/views/window/dialog_delegate.h"
 
@@ -37,7 +38,6 @@ namespace {
 // destroyed before a box in an outer-loop. So to avoid this, ref-counting is
 // used so that the SimpleMessageBoxViews gets deleted at the right time.
 class SimpleMessageBoxViews : public views::DialogDelegate,
-                              public base::MessagePumpDispatcher,
                               public base::RefCounted<SimpleMessageBoxViews> {
  public:
   SimpleMessageBoxViews(const base::string16& title,
@@ -63,13 +63,13 @@ class SimpleMessageBoxViews : public views::DialogDelegate,
   virtual views::Widget* GetWidget() OVERRIDE;
   virtual const views::Widget* GetWidget() const OVERRIDE;
 
-  // Overridden from MessagePumpDispatcher:
-  virtual uint32_t Dispatch(const base::NativeEvent& event) OVERRIDE;
-
  private:
   friend class base::RefCounted<SimpleMessageBoxViews>;
   virtual ~SimpleMessageBoxViews();
 
+  // This terminates the nested message-loop.
+  void Done();
+
   const base::string16 window_title_;
   const MessageBoxType type_;
   base::string16 yes_text_;
@@ -77,10 +77,6 @@ class SimpleMessageBoxViews : public views::DialogDelegate,
   MessageBoxResult result_;
   views::MessageBoxView* message_box_view_;
 
-  // Set to false as soon as the user clicks a dialog button; this tells the
-  // dispatcher we're done.
-  bool should_show_dialog_;
-
   DISALLOW_COPY_AND_ASSIGN(SimpleMessageBoxViews);
 };
 
@@ -98,8 +94,7 @@ SimpleMessageBoxViews::SimpleMessageBoxViews(const base::string16& title,
       no_text_(no_text),
       result_(MESSAGE_BOX_RESULT_NO),
       message_box_view_(new views::MessageBoxView(
-          views::MessageBoxView::InitParams(message))),
-      should_show_dialog_(true) {
+          views::MessageBoxView::InitParams(message))) {
   AddRef();
 
   if (yes_text_.empty()) {
@@ -138,14 +133,14 @@ base::string16 SimpleMessageBoxViews::GetDialogButtonLabel(
 }
 
 bool SimpleMessageBoxViews::Cancel() {
-  should_show_dialog_= false;
   result_ = MESSAGE_BOX_RESULT_NO;
+  Done();
   return true;
 }
 
 bool SimpleMessageBoxViews::Accept() {
-  should_show_dialog_ = false;
   result_ = MESSAGE_BOX_RESULT_YES;
+  Done();
   return true;
 }
 
@@ -173,13 +168,6 @@ const views::Widget* SimpleMessageBoxViews::GetWidget() const {
   return message_box_view_->GetWidget();
 }
 
-uint32_t SimpleMessageBoxViews::Dispatch(const base::NativeEvent& event) {
-  uint32_t action = POST_DISPATCH_PERFORM_DEFAULT;
-  if (!should_show_dialog_)
-    action |= POST_DISPATCH_QUIT_LOOP;
-  return action;
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // SimpleMessageBoxViews, private:
 
@@ -204,6 +192,21 @@ UINT GetMessageBoxFlagsFromType(MessageBoxType type) {
 }
 #endif
 
+void SimpleMessageBoxViews::Done() {
+  // The nested-loop is started from the parent's dispatcher client (if there is
+  // one), otherwise it's started from the widget's own window's dispatcher
+  // client. Make sure the termination of the nested loop happens from the
+  // correct dispatcher client.
+  aura::Window* window = GetWidget()->GetNativeView();
+  aura::Window* parent = views::corewm::GetTransientParent(window);
+  aura::client::DispatcherClient* client = NULL;
+  if (parent)
+    client = aura::client::GetDispatcherClient(parent->GetRootWindow());
+  if (!client)
+    client = aura::client::GetDispatcherClient(window->GetRootWindow());
+  client->QuitNestedMessageLoop();
+}
+
 MessageBoxResult ShowMessageBoxImpl(gfx::NativeWindow parent,
                                     const base::string16& title,
                                     const base::string16& message,
@@ -234,7 +237,7 @@ MessageBoxResult ShowMessageBoxImpl(gfx::NativeWindow parent,
     anchor = dialog->GetWidget()->GetNativeWindow();
     client = aura::client::GetDispatcherClient(anchor->GetRootWindow());
   }
-  client->RunWithDispatcher(dialog.get(), anchor);
+  client->RunWithDispatcher(NULL, anchor);
   return dialog->result();
 }