Fixed a fullscreen race condition on OSX

chrome/browser/ui/cocoa/browser_window_controller_private.mm

Index: chrome/browser/ui/cocoa/browser_window_controller_private.mm
diff --git a/chrome/browser/ui/cocoa/browser_window_controller_private.mm b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
index ebb3bd4f108bc7b2d6d7d13a286aa63e0e570e3e..826b0c2e1119bdef5994af08b2059f8bc68044aa 100644
--- a/chrome/browser/ui/cocoa/browser_window_controller_private.mm
+++ b/chrome/browser/ui/cocoa/browser_window_controller_private.mm
@@ -21,7 +21,6 @@
 #include "chrome/browser/ui/bookmarks/bookmark_tab_helper.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/browser_window_state.h"
-#import "chrome/browser/ui/cocoa/browser_window_fullscreen_transition.h"
 #import "chrome/browser/ui/cocoa/browser_window_layout.h"
 #import "chrome/browser/ui/cocoa/browser/exclusive_access_controller_views.h"
 #import "chrome/browser/ui/cocoa/constrained_window/constrained_window_sheet_controller.h"
@@ -778,6 +777,15 @@ willPositionSheet:(NSWindow*)sheet
 - (void)windowDidExitFullScreen:(NSNotification*)notification {
   DCHECK(exitingAppKitFullscreen_);
 
+  // If the custom transition isn't complete, then just set the flag and
+  // return. Once the transition is completed, windowDidExitFullscreen will
+  // be called again.
+  if (isUsingCustomAnimation_ &&
+      ![fullscreenTransition_ isTransitionCompleted]) {
+    appKitDidExitFullscreen_ = YES;
+    return;
+  }
+
   if (notification)  // For System Fullscreen when non-nil.
     [self deregisterForContentViewResizeNotifications];
 
@@ -1196,6 +1204,7 @@ willPositionSheet:(NSWindow*)sheet
       base::mac::ObjCCast<FramedBrowserWindow>([self window]);
   fullscreenTransition_.reset([[BrowserWindowFullscreenTransition alloc]
           initExitWithWindow:framedBrowserWindow
+                    delegate:self
                        frame:savedRegularWindowFrame_
       tabStripBackgroundView:[self tabStripBackgroundView]]);