Upgrade WebGLImageConversion to ES3: Part I.

Source/platform/graphics/gpu/WebGLImageConversion.h

 // Copyright 2014 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.
 
 #ifndef WebGLImageConversion_h
 #define WebGLImageConversion_h
 
 #include "platform/PlatformExport.h"
 #include "platform/graphics/Image.h"
 #include "third_party/khronos/GLES2/gl2.h"
@@ skipping 33 matching lines @@
         DataFormatRGB16F,
         DataFormatRGB32F,
         DataFormatBGR8,
         DataFormatBGRA8,
         DataFormatARGB8,
         DataFormatABGR8,
         DataFormatRGBA5551,
         DataFormatRGBA4444,
         DataFormatRGB565,
         DataFormatRGB10F11F11F,
+        DataFormatRGB5999,
         DataFormatRG8,
         DataFormatRG8_S,
         DataFormatRG16,
         DataFormatRG16_S,
         DataFormatRG32,
         DataFormatRG32_S,
         DataFormatRG16F,
         DataFormatRG32F,
         DataFormatR8,
         DataFormatR8_S,
@@ skipping 129 matching lines @@
     // A sourceUnpackAlignment of zero indicates that the source
     // data is tightly packed. Non-zero values may take a slow path.
     // Destination data will have no gaps between rows.
     // Implemented in GraphicsContext3DImagePacking.cpp
     static bool packPixels(const uint8_t* sourceData, DataFormat sourceDataFormat, unsigned width, unsigned height, unsigned sourceUnpackAlignment, unsigned destinationFormat, unsigned destinationType, AlphaOp, void* destinationData, bool flipY);
 };
 
 } // namespace blink
 
 #endif // WebGLImageConversion_h