gpu: Make sure external texture destination is initialized

gpu/command_buffer/service/gles2_cmd_decoder.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/gles2_cmd_decoder.h"
 
 #include <stdio.h>
 
 #include <algorithm>
 #include <list>
@@ skipping 9609 matching lines @@
   bool dest_level_defined = dest_texture->GetLevelSize(
       GL_TEXTURE_2D, level, &dest_width, &dest_height);
 
   if (dest_level_defined) {
     dest_texture->GetLevelType(GL_TEXTURE_2D, level, &dest_type_previous,
                                &dest_internal_format);
   }
 
   // Set source texture's width and height to be the same as
   // destination texture when source is GL_TEXTURE_EXTERNAL_OES.
   if (source_texture->target() == GL_TEXTURE_EXTERNAL_OES) {

[greggman, 2013/05/09 16:15:11]

Doesn't this code just need to move to about line 9665? The code at line 9641
will make the level exist

[Sami, 2013/05/09 16:18:43]

The problem is that for GL_TEXTURE_EXTERNAL, source_width and source_height are
both undefined so we can't really initialize the destination level directly. See
the comment on line 9579.

+    if (!dest_level_defined) {

[greggman, 2013/05/09 16:41:23]

Then please add a TODO: here that this coude should be removed. The contact for
CopyTextureCHROMIUM is that it creates the level. The client shouldn't have to
know the size. The comment above even says they need to provide a way to get the
width/height

[Sami, 2013/05/09 16:46:24]

Right, this is just a temporary safeguard while this code exist. I've duplicated
the TODO from above here.

+      LOCAL_SET_GL_ERROR(
+          GL_INVALID_VALUE,
+          "glCopyTextureCHROMIUM", "destination level not defined");
+      return;
+    }
     source_width = dest_width;
     source_height = dest_height;
   }
 
   // Resize the destination texture to the dimensions of the source texture.
   if (!dest_level_defined || dest_width != source_width ||
       dest_height != source_height ||
       dest_internal_format != internal_format ||
       dest_type_previous != dest_type) {
     // Ensure that the glTexImage2D succeeds.
@@ skipping 691 matching lines @@
   return error::kNoError;
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu