Fix glTexSubImage2D for non-32bpp formats.

cc/texture.cc

 // Copyright 2012 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.
 
 #include "config.h"
 
 #include "cc/texture.h"
+#include "third_party/khronos/GLES2/gl2ext.h"
 
 namespace cc {
 
 void CCTexture::setDimensions(const IntSize& size, GLenum format)
 {
     m_size = size;
     m_format = format;
 }
 
 size_t CCTexture::bytes() const
 {
     if (m_size.isEmpty())
         return 0u;
 
     return memorySizeBytes(m_size, m_format);
 }
 
+size_t CCTexture::bytesPerPixel(GLenum format)
+{
+    unsigned int componentsPerPixel = 0;
+    unsigned int bytesPerComponent = 1;
+    switch (format) {
+    case GL_RGBA:
+    case GL_BGRA_EXT:
+        componentsPerPixel = 4;
+        break;
+    case GL_LUMINANCE:
+        componentsPerPixel = 1;
+        break;
+    default:
+        NOTREACHED();
+    }
+    return componentsPerPixel * bytesPerComponent;
+}
+
 size_t CCTexture::memorySizeBytes(const IntSize& size, GLenum format)
 {
-    unsigned int componentsPerPixel = 4;
-    unsigned int bytesPerComponent = 1;
-    return componentsPerPixel * bytesPerComponent * size.width() * size.height();
+    return bytesPerPixel(format) * size.width() * size.height();
 }
 
 }