Fixing issues using TexStorage2D with compressed textures

Source/modules/webgl/WebGLRenderingContextBase.cpp

 /*
  * 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 1806 matching lines @@
         synthesizeGLError(GL_INVALID_ENUM, "compressedTexSubImage2D", "invalid format");
         return;
     }
     if (!validateCompressedTexFuncData("compressedTexSubImage2D", width, height, format, data))
         return;
 
     WebGLTexture* tex = validateTextureBinding("compressedTexSubImage2D", target, true);
     if (!tex)
         return;
 
-    if (format != tex->getInternalFormat(target, level)) {
+    if (!isWebGL2OrHigher() && format != tex->getInternalFormat(target, level)) {

[Zhenyao Mo, 2015/07/29 20:57:57]

It might be OK for now, but we do need to validate (internal_format, format)
combination for WebGL 2 here. In general, we should validate everything in
WebGLRenderingContext.

         synthesizeGLError(GL_INVALID_OPERATION, "compressedTexSubImage2D", "format does not match texture format");
         return;
     }
 
     if (!validateCompressedTexSubDimensions("compressedTexSubImage2D", target, level, xoffset, yoffset, width, height, format, tex))
         return;
 
     webContext()->compressedTexSubImage2D(target, level, xoffset, yoffset,
         width, height, format, data->byteLength(), data->baseAddress());
 }
@@ skipping 4757 matching lines @@
 
     return totalBytesPerPixel;
 }
 
 DrawingBuffer* WebGLRenderingContextBase::drawingBuffer() const
 {
     return m_drawingBuffer.get();
 }
 
 } // namespace blink