Add OES_texture_half_float extension support in WebGL.

Source/core/html/canvas/WebGLRenderingContext.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 3672 matching lines @@
 
     if (m_unpackAlignment != 1)
         m_context->pixelStorei(GraphicsContext3D::UNPACK_ALIGNMENT, 1);
     texImage2DBase(target, level, internalformat, image->width(), image->height(), 0, format, type, needConversion ? data.data() : imagePixelData, ec);
     if (m_unpackAlignment != 1)
         m_context->pixelStorei(GraphicsContext3D::UNPACK_ALIGNMENT, m_unpackAlignment);
 }
 
 bool WebGLRenderingContext::validateTexFunc(const char* functionName, TexFuncValidationFunctionType functionType, TexFuncValidationSourceType sourceType, GC3Denum target, GC3Dint level, GC3Denum internalformat, GC3Dsizei width, GC3Dsizei height, GC3Dint border, GC3Denum format, GC3Denum type, GC3Dint xoffset, GC3Dint yoffset)
 {
-    // FIXME: Uploading {ImageData, HTMLImageElement, HTMLCanvasElement, HTMLVideoElement} to half floating point texture is not supported yet.
-    // See https://bugs.webkit.org/show_bug.cgi?id=110936.
-    if (sourceType != SourceArrayBufferView && type == GraphicsContext3D::HALF_FLOAT_OES) {
-        synthesizeGLError(GraphicsContext3D::INVALID_OPERATION, functionName, "Operation not supported yet");
-        return false;
-    }
-
     if (!validateTexFuncParameters(functionName, functionType, target, level, internalformat, width, height, border, format, type))
         return false;
 
     WebGLTexture* texture = validateTextureBinding(functionName, target, true);
     if (!texture)
         return false;
 
     if (functionType == NotTexSubImage2D) {
         if (level && WebGLTexture::isNPOT(width, height)) {
             synthesizeGLError(GraphicsContext3D::INVALID_VALUE, functionName, "level > 0 not power of 2");
@@ skipping 2292 matching lines @@
 bool WebGLRenderingContext::supportsDrawBuffers()
 {
     if (!m_drawBuffersWebGLRequirementsChecked) {
         m_drawBuffersWebGLRequirementsChecked = true;
         m_drawBuffersSupported = EXTDrawBuffers::supported(this);
     }
     return m_drawBuffersSupported;
 }
 
 } // namespace WebCore