gpu: Use a rectangle to keep track of the cleared area of each texture level.

gpu/command_buffer/service/texture_definition.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 GPU_COMMAND_BUFFER_SERVICE_TEXTURE_DEFINITION_H_
 #define GPU_COMMAND_BUFFER_SERVICE_TEXTURE_DEFINITION_H_
 
 #include <vector>
 
 #include "base/memory/ref_counted.h"
 #include "gpu/command_buffer/service/gl_utils.h"
+#include "ui/gfx/geometry/rect.h"
 
 namespace gfx {
 class GLImage;
 }
 
 namespace gpu {
 namespace gles2 {
 
 class Texture;
 
@@ skipping 55 matching lines @@
   struct LevelInfo {
     LevelInfo();
     LevelInfo(GLenum target,
               GLenum internal_format,
               GLsizei width,
               GLsizei height,
               GLsizei depth,
               GLint border,
               GLenum format,
               GLenum type,
-              bool cleared);
+              const gfx::Rect& cleared_rect);
     ~LevelInfo();
 
     GLenum target;
     GLenum internal_format;
     GLsizei width;
     GLsizei height;
     GLsizei depth;
     GLint border;
     GLenum format;
     GLenum type;
-    bool cleared;
+    gfx::Rect cleared_rect;
   };
 
   unsigned int version_;
   GLenum target_;
   scoped_refptr<NativeImageBuffer> image_buffer_;
   GLenum min_filter_;
   GLenum mag_filter_;
   GLenum wrap_s_;
   GLenum wrap_t_;
   GLenum usage_;
   bool immutable_;
   bool defined_;
 
   // Only support textures with one face and one level.
   LevelInfo level_info_;
 };
 
 }  // namespage gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_TEXTURE_DEFINITION_H_