[rAC, OSX] Use bubble windows for error messages.

chrome/browser/ui/cocoa/base_bubble_controller.mm

 // 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.
 
 #import "chrome/browser/ui/cocoa/base_bubble_controller.h"
 
 #include "base/logging.h"
 #include "base/mac/bundle_locations.h"
 #include "base/mac/mac_util.h"
 #include "base/mac/scoped_nsobject.h"
@@ skipping 192 matching lines @@
   NSNotification* note =
       [NSNotification notificationWithName:NSWindowDidResignKeyNotification
                                     object:window];
 
   // The eventTap_ catches clicks within the application that are outside the
   // window.
   eventTap_ = [NSEvent
       addLocalMonitorForEventsMatchingMask:NSLeftMouseDownMask
       handler:^NSEvent* (NSEvent* event) {
           if (event.window != window) {
+            // Ignore this event if the window isn't key - in that case, it
+            // can't resign key status in the first place.
+            if (![window isKeyWindow])
+              return event;
+
             // Call via the runloop because this block is called in the
             // middle of event dispatch.
             [self performSelector:@selector(windowDidResignKey:)
                        withObject:note
                        afterDelay:0];
           }
           return event;
       }];
 
   // The resignationObserver_ watches for when a window resigns key state,
@@ skipping 61 matching lines @@
 
 - (void)activateTabWithContents:(content::WebContents*)newContents
                previousContents:(content::WebContents*)oldContents
                         atIndex:(NSInteger)index
                          reason:(int)reason {
   // The user switched tabs; close.
   [self close];
 }
 
 @end  // BaseBubbleController