events: Remove ability to terminate a nested message-loop from the event-source.

ui/events/platform/platform_event_dispatcher.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_EVENTS_PLATFORM_PLATFORM_EVENT_DISPATCHER_H_
 #define UI_EVENTS_PLATFORM_PLATFORM_EVENT_DISPATCHER_H_
 
 #include "base/basictypes.h"
 #include "ui/events/events_export.h"
 #include "ui/events/platform/platform_event_types.h"
 
 namespace ui {
 
 // See documentation for |PlatformEventDispatcher::DispatchEvent()| for
 // explanation of the meaning of the flags.
 enum PostDispatchAction {
   POST_DISPATCH_NONE = 0x0,
-  POST_DISPATCH_QUIT_LOOP = 0x1,
-  POST_DISPATCH_PERFORM_DEFAULT = 0x2,
-  POST_DISPATCH_STOP_PROPAGATION = 0x4,
+  POST_DISPATCH_PERFORM_DEFAULT = 0x1,
+  POST_DISPATCH_STOP_PROPAGATION = 0x2,
 };
 
 // PlatformEventDispatcher receives events from a PlatformEventSource and
 // dispatches them.
 class EVENTS_EXPORT PlatformEventDispatcher {
  public:
   // Returns whether this dispatcher wants to dispatch |event|.
   virtual bool CanDispatchEvent(const PlatformEvent& event) = 0;
 
   // Dispatches |event|. If this is not the default dispatcher, then the
   // dispatcher can request that the default dispatcher gets a chance to
   // dispatch the event by setting POST_DISPATCH_PERFORM_DEFAULT to the return
-  // value. If a nested message-loop is active, then the dispatcher can signal
-  // that the nested message-loop should be terminated by setting
-  // POST_DISPATCH_QUIT_LOOP flag on the return value. If the dispatcher has
-  // processed the event, and no other dispatcher should be allowed to dispatch
-  // the event, then the dispatcher should set POST_DISPATCH_STOP_PROPAGATION
-  // flag on the return value.
+  // value. If the dispatcher has processed the event, and no other dispatcher
+  // should be allowed to dispatch the event, then the dispatcher should set
+  // POST_DISPATCH_STOP_PROPAGATION flag on the return value.
   virtual uint32_t DispatchEvent(const PlatformEvent& event) = 0;
 
  protected:
   virtual ~PlatformEventDispatcher() {}
 };
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_PLATFORM_PLATFORM_EVENT_DISPATCHER_H_