Add glCompressedCopySubTextureCHROMIUM

gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc

Index: gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
diff --git a/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc b/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
index 6199dfaa0db7c4ebf75925f176b5565f597253ea..a987a39ce37e1c86113b443cfed9e602d9987557 100644
--- a/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
+++ b/gpu/command_buffer/service/gles2_cmd_copy_texture_chromium.cc
@@ -471,8 +471,10 @@ void CopyTextureCHROMIUMResourceManager::DoCopyTextureInternal(
   DCHECK(source_target == GL_TEXTURE_2D ||
          source_target == GL_TEXTURE_RECTANGLE_ARB ||
          source_target == GL_TEXTURE_EXTERNAL_OES);
-  DCHECK(xoffset >= 0 && xoffset + source_width <= dest_width);
-  DCHECK(yoffset >= 0 && yoffset + source_height <= dest_height);
+  DCHECK_GE(xoffset, 0);
+  DCHECK_LE(xoffset + width, dest_width);
+  DCHECK_GE(yoffset, 0);
+  DCHECK_LE(yoffset + height, dest_height);
   if (!initialized_) {
     DLOG(ERROR) << "CopyTextureCHROMIUM: Uninitialized manager.";
     return;