Mac: Recreate browser-side GL contexts on GPU switch

content/browser/renderer_host/compositing_iosurface_layer_mac.mm

 // Copyright 2013 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.
 
 #include "content/browser/renderer_host/compositing_iosurface_layer_mac.h"
 
 #include <CoreFoundation/CoreFoundation.h>
 #include <OpenGL/gl.h>
 
 #include "base/mac/mac_util.h"
@@ skipping 24 matching lines @@
     if (renderWidgetHostView_->compositing_iosurface_ &&
         [self respondsToSelector:(@selector(setContentsScale:))]) {
       [self setContentsScale:
           renderWidgetHostView_->compositing_iosurface_->scale_factor()];
     }
   }
   return self;
 }
 
 - (void)disableCompositing{
-  // Disable the fade-out animation as the layer is removed.
-  ScopedCAActionDisabler disabler;
-  [self removeFromSuperlayer];

[ccameron, 2014/04/09 22:06:01]

This was always done by the caller, so it was redundant.

   renderWidgetHostView_ = nil;
 }
 
 - (void)gotNewFrame {
   if (context_ && context_->is_vsync_disabled()) {
     // If vsync is disabled, draw immediately and don't bother trying to use
     // the isAsynchronous property to ensure smooth animation.
     [self setNeedsDisplay];
     [self displayIfNeeded];
 
@@ skipping 92 matching lines @@
   renderWidgetHostView_->SendPendingLatencyInfoToHost();
   renderWidgetHostView_->SendPendingSwapAck();
 
   [super drawInCGLContext:glContext
               pixelFormat:pixelFormat
              forLayerTime:timeInterval
               displayTime:timeStamp];
 }
 
 @end