Limit the number of WebGL contexts that are active at any given time

Source/core/html/canvas/WebGLRenderingContext.h

 /*
  * Copyright (C) 2009 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 755 matching lines @@
 
     void setBackDrawBuffer(GC3Denum);
 
     void restoreCurrentFramebuffer();
     void restoreCurrentTexture2D();
 
     // Check if EXT_draw_buffers extension is supported and if it satisfies the WebGL requirements.
     bool supportsDrawBuffers();
 
     friend class WebGLStateRestorer;
+    friend class WebGLRenderingContextEvictionManager;
+
+    static Vector<WebGLRenderingContext*>& activeContexts();
+    static Vector<WebGLRenderingContext*>& forciblyEvictedContexts();
+
+    static void activateContext(WebGLRenderingContext*);
+    static void deactivateContext(WebGLRenderingContext*, bool addToInactiveList);
+    static void willDestroyContext(WebGLRenderingContext*);
+    static void forciblyLoseOldestContext(const String& reason);
+    static IntSize oldestContextSize();
 };
 
 } // namespace WebCore
 
 #endif