Simplify fullscreen exit bubble on mac; updating always creates one freshly.

chrome/browser/ui/cocoa/browser_window_controller_private.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/browser_window_controller_private.h"
 
 #include <cmath>
 
 #include "base/command_line.h"
 #import "base/memory/scoped_nsobject.h"
@@ skipping 775 matching lines @@
   NSView* infoBarDest = [[self window] contentView];
   [infoBarDest addSubview:[infoBarContainerController_ view]
                positioned:fullscreen ? NSWindowBelow : NSWindowAbove
                relativeTo:fullscreen ? nil
                                      : [toolbarController_ view]];
 }
 
 - (void)showFullscreenExitBubbleIfNecessary {
   [presentationModeController_ ensureOverlayHiddenWithAnimation:NO delay:NO];
 
-  [fullscreenExitBubbleController_ closeImmediately];
-  fullscreenExitBubbleController_.reset(
-      [[FullscreenExitBubbleController alloc]
-          initWithOwner:self
-                browser:browser_.get()
-                    url:fullscreenUrl_
-             bubbleType:fullscreenBubbleType_]);
-  [fullscreenExitBubbleController_ showWindow];
+  if (fullscreenBubbleType_ == FEB_TYPE_NONE ||
+      fullscreenBubbleType_ == FEB_TYPE_BROWSER_FULLSCREEN_EXIT_INSTRUCTION) {
+    // Show no exit instruction bubble on Mac when in Browser Fullscreen.
+    [self destroyFullscreenExitBubbleIfNecessary];
+  } else {
+    [fullscreenExitBubbleController_ closeImmediately];
+    fullscreenExitBubbleController_.reset(
+        [[FullscreenExitBubbleController alloc]
+            initWithOwner:self
+                  browser:browser_.get()
+                      url:fullscreenUrl_
+               bubbleType:fullscreenBubbleType_]);
+    [fullscreenExitBubbleController_ showWindow];
+  }
 }
 
 - (void)destroyFullscreenExitBubbleIfNecessary {
   [fullscreenExitBubbleController_ closeImmediately];
   fullscreenExitBubbleController_.reset();
 }
 
 - (void)contentViewDidResize:(NSNotification*)notification {
   [self layoutSubviews];
 }
@@ skipping 89 matching lines @@
 - (void)disableBarVisibilityUpdates {
   // Early escape if there's nothing to do.
   if (!barVisibilityUpdatesEnabled_)
     return;
 
   barVisibilityUpdatesEnabled_ = NO;
   [presentationModeController_ cancelAnimationAndTimers];
 }
 
 @end  // @implementation BrowserWindowController(Private)