base: Do not allow MessagePumpObservers to consume events.

chrome/browser/ui/views/tabs/tab_drag_controller.cc

 // Copyright (c) 2012 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.
 
 #include "chrome/browser/ui/views/tabs/tab_drag_controller.h"
 
 #include <math.h>
 #include <set>
 
 #include "base/auto_reset.h"
@@ skipping 475 matching lines @@
       return;
     }
   }
   // If we get here it means we got notification for a tab we don't know about.
   NOTREACHED();
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // TabDragController, MessageLoop::Observer implementation:
 
-base::EventStatus TabDragController::WillProcessEvent(
-    const base::NativeEvent& event) {
-  return base::EVENT_CONTINUE;
-}
+void TabDragController::WillProcessEvent(const base::NativeEvent& event) {}
 
 void TabDragController::DidProcessEvent(const base::NativeEvent& event) {
   // If the user presses ESC during a drag, we need to abort and revert things
   // to the way they were. This is the most reliable way to do this since no
   // single view or window reliably receives events throughout all the various
   // kinds of tab dragging.
   if (ui::EventTypeFromNative(event) == ui::ET_KEY_PRESSED &&
       ui::KeyboardCodeFromNative(event) == ui::VKEY_ESCAPE) {
     EndDrag(END_DRAG_CANCEL);
   }
@@ skipping 1412 matching lines @@
        it != browser_list->end(); ++it) {
     if ((*it)->tab_strip_model()->empty())
       exclude.insert((*it)->window()->GetNativeWindow());
   }
 #endif
   return GetLocalProcessWindowAtPoint(host_desktop_type_,
                                       screen_point,
                                       exclude);
 
 }