Implemented fullscreen exit animation with AppKit

chrome/browser/ui/cocoa/full_size_content_window.mm

Index: chrome/browser/ui/cocoa/full_size_content_window.mm
diff --git a/chrome/browser/ui/cocoa/full_size_content_window.mm b/chrome/browser/ui/cocoa/full_size_content_window.mm
index 1dea52a7000bd65d1d62417433394e089eb08e28..eebce5415da881dda3e10da159a06fc0fd38160d 100644
--- a/chrome/browser/ui/cocoa/full_size_content_window.mm
+++ b/chrome/browser/ui/cocoa/full_size_content_window.mm
@@ -15,8 +15,6 @@
 // This view always takes the size of its superview. It is intended to be used
 // as a NSWindow's contentView.  It is needed because NSWindow's implementation
 // explicitly resizes the contentView at inopportune times.
-@interface FullSizeContentView : NSView
-@end
 
 @implementation FullSizeContentView
 
@@ -28,6 +26,10 @@
   [super setFrameSize:size];
 }
 
+- (void)forceFrameSize:(NSSize)size {
+  [super setFrameSize:size];
+}
+
 @end
 
 @implementation FullSizeContentWindow