glBindTexImage2DCHROMIUM should retain pixel format.

ui/gl/gl_image.h

 // Copyright (c) 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.
 
 #ifndef UI_GL_GL_IMAGE_H_
 #define UI_GL_GL_IMAGE_H_
 
 #include "base/memory/ref_counted.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/rect_f.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/overlay_transform.h"
 #include "ui/gl/gl_export.h"
 
 namespace gfx {
 
 // Encapsulates an image that can be bound to a texture, hiding platform
 // specific management.
 class GL_EXPORT GLImage : public base::RefCounted<GLImage> {
  public:
   GLImage() {}
 
   // Destroys the image.
   virtual void Destroy(bool have_context) = 0;
 
   // Get the size of the image.
   virtual gfx::Size GetSize() = 0;
 
+  // Get the image pixel format.

[reveman, 2015/05/12 15:27:19]

Internal format is not guaranteed to match the exact pixel format. "Get the
internal format of the image."?

[christiank, 2015/05/13 09:02:23]

Alright, I was debating whether using GetInternalFormat was the right way to go
here. But I was unsure whether the concept existed for GLImage. Should now be
fixed.

+  virtual unsigned GetFormat() = 0;

[reveman, 2015/05/12 15:27:19]

nit: GetInternalFormat() as that's how we refer to this in CHROMIUM_image spec:

https://code.google.com/p/chromium/codesearch#chromium/src/gpu/GLES2/extensio...

+
   // Bind image to texture currently bound to |target|.
   virtual bool BindTexImage(unsigned target) = 0;
 
   // Release image from texture currently bound to |target|.
   virtual void ReleaseTexImage(unsigned target) = 0;
 
   // Copy image to texture currently bound to |target|.
   virtual bool CopyTexImage(unsigned target) = 0;
 
   // Called before the texture is used for drawing.
@@ skipping 20 matching lines @@
 
  private:
   friend class base::RefCounted<GLImage>;
 
   DISALLOW_COPY_AND_ASSIGN(GLImage);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GL_GL_IMAGE_H_