Changed GL enums from GraphicsContext3D to standard versions (Take 2)

Source/platform/graphics/GraphicsTypes3D.h

 /*
  * Copyright (C) 2011 Google 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 11 matching lines @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef GraphicsTypes3D_h
 #define GraphicsTypes3D_h
 
 #include "wtf/Forward.h"
 #include <stdint.h>
 
-// GC3D types match the corresponding GL types as defined in OpenGL ES 2.0
-// header file gl2.h from khronos.org.
+// GC3D types and enums match the corresponding GL types and enums as defined
+// in OpenGL ES 2.0 header file gl2.h from khronos.org.
 typedef unsigned GC3Denum;
 typedef unsigned char GC3Dboolean;
 typedef unsigned GC3Dbitfield;
 typedef signed char GC3Dbyte;
 typedef unsigned char GC3Dubyte;
 typedef short GC3Dshort;
 typedef unsigned short GC3Dushort;
 typedef int GC3Dint;
 typedef int GC3Dsizei;
 typedef unsigned GC3Duint;
 typedef float GC3Dfloat;
 typedef unsigned short GC3Dhalffloat;
 typedef float GC3Dclampf;
 typedef intptr_t GC3Dintptr;
 typedef intptr_t GC3Dsizeiptr;
 typedef char GC3Dchar;
 
 typedef GC3Duint Platform3DObject;
 
+// WebGL-specific enums
+const GC3Denum GC3D_DEPTH_STENCIL_ATTACHMENT_WEBGL = 0x821A;
+const GC3Denum GC3D_UNPACK_FLIP_Y_WEBGL = 0x9240;
+const GC3Denum GC3D_UNPACK_PREMULTIPLY_ALPHA_WEBGL = 0x9241;
+const GC3Denum GC3D_CONTEXT_LOST_WEBGL = 0x9242;
+const GC3Denum GC3D_UNPACK_COLORSPACE_CONVERSION_WEBGL = 0x9243;
+const GC3Denum GC3D_BROWSER_DEFAULT_WEBGL = 0x9244;
+
 #endif