Use gfx::Rect::Intersect() to clip for CopyTex{Sub}Image functions.

gpu/command_buffer/service/texture_manager.cc

 // 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.
 
 #include "gpu/command_buffer/service/texture_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 1097 matching lines @@
     GLsizei width,
     GLsizei height,
     GLsizei depth) const {
   size_t face_index = GLES2Util::GLTargetToFaceIndex(target);
   if (level >= 0 && face_index < face_infos_.size() &&
       static_cast<size_t>(level) < face_infos_[face_index].level_infos.size()) {
     const LevelInfo& info = face_infos_[face_index].level_infos[level];
     int32_t max_x;
     int32_t max_y;
     int32_t max_z;
-    return SafeAddInt32(xoffset, width, &max_x) &&
+    return xoffset >= 0 &&
+           yoffset >= 0 &&
+           zoffset >= 0 &&
+           width >= 0 &&
+           height >= 0 &&
+           depth >= 0 &&
+           SafeAddInt32(xoffset, width, &max_x) &&
            SafeAddInt32(yoffset, height, &max_y) &&
            SafeAddInt32(zoffset, depth, &max_z) &&
-           xoffset >= 0 &&
-           yoffset >= 0 &&
-           zoffset >= 0 &&
            max_x <= info.width &&
            max_y <= info.height &&
            max_z <= info.depth;
   }
   return false;
 }
 
 bool Texture::GetLevelSize(
     GLint target, GLint level,
     GLsizei* width, GLsizei* height, GLsizei* depth) const {
@@ skipping 2343 matching lines @@
 uint32_t TextureManager::GetServiceIdGeneration() const {
   return current_service_id_generation_;
 }
 
 void TextureManager::IncrementServiceIdGeneration() {
   current_service_id_generation_++;
 }
 
 }  // namespace gles2
 }  // namespace gpu