Fix OSX 10.12 compilation errors in chrome/browser/ui.

chrome/browser/ui/cocoa/browser_window_fullscreen_transition.mm

 // Copyright 2015 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_fullscreen_transition.h"
 
 #include <QuartzCore/QuartzCore.h>
 
 #include <memory>
 
@@ skipping 70 matching lines @@
   NSRectFillUsingOperation(frame, NSCompositeDestinationOver);
 
   [FramedBrowserWindow drawWindowThemeInDirtyRect:frame
                                           forView:self
                                            bounds:[self bounds]
                              forceBlackBackground:NO];
 }
 
 @end
 
-@interface BrowserWindowFullscreenTransition () {
+@interface BrowserWindowFullscreenTransition ()
+    <CAAnimationDelegate, CALayerDelegate> {
   // Flag to keep track of whether we are entering or exiting fullscreen.
   BOOL isEnteringFullscreen_;
 
   // The window which is undergoing the fullscreen transition.
   base::scoped_nsobject<FramedBrowserWindow> primaryWindow_;
 
   // The window which is undergoing the fullscreen transition.
   BrowserWindowController* controller_; // weak
 
   // A layer that holds a snapshot of the original state of |primaryWindow_|.
@@ skipping 55 matching lines @@
 //    - Add NSFullScreenWindowMask style mask.
 //    - Set the size to the screen's size.
 - (void)preparePrimaryWindowForAnimation;
 
 // Applies the fullscreen animation to |snapshotLayer_|.
 - (void)animateSnapshotWindowWithDuration:(CGFloat)duration;
 
 // Sets |primaryWindow_|'s frame to the expected frame.
 - (void)changePrimaryWindowToFinalFrame;
 
-// Override of CAAnimation delegate method.
+// Overrides of CAAnimation delegate methods.
+- (void)animationDidStart:(CAAnimation*)theAnimation;
 - (void)animationDidStop:(CAAnimation*)theAnimation finished:(BOOL)finished;
 
 // Returns the layer of the root view of |window|.
 - (CALayer*)rootLayerOfWindow:(NSWindow*)window;
 
 // Convert the point to be relative to the screen the primary window is on.
 // This is important because if we're using multiple screens, the coordinate
 // system extends to the second screen.
 //
 // For example, if the screen width is 1440, the second screen's frame origin
@@ skipping 297 matching lines @@
   CALayer* root = [self rootLayerOfWindow:primaryWindow_];
   [root addAnimation:group forKey:kPrimaryWindowAnimationID];
 }
 
 - (void)changePrimaryWindowToFinalFrame {
   changingPrimaryWindowSize_ = YES;
   [primaryWindow_ setFrame:finalFrame_ display:NO];
   changingPrimaryWindowSize_ = NO;
 }
 
+- (void)animationDidStart:(CAAnimation*)theAnimation {
+  // CAAnimationDelegate method added on OSX 10.12.
+}
+
 - (void)animationDidStop:(CAAnimation*)theAnimation finished:(BOOL)finished {
   NSString* animationID = [theAnimation valueForKey:kAnimationIDKey];
 
   // Remove the snapshot window.
   if ([animationID isEqual:kSnapshotWindowAnimationID]) {
     [snapshotWindow_ orderOut:nil];
     snapshotWindow_.reset();
     snapshotLayer_.reset();
     return;
   }
@@ skipping 49 matching lines @@
   return [[[window contentView] superview] layer];
 }
 
 - (NSPoint)pointRelativeToCurrentScreen:(NSPoint)point {
   NSRect screenFrame = [[primaryWindow_ screen] frame];
   return NSMakePoint(point.x - screenFrame.origin.x,
                      point.y - screenFrame.origin.y);
 }
 
 @end