Added FBO Invalidation workaround for Nexus 6.

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 4474 matching lines @@
   } else {
     LOCAL_SET_GL_ERROR(
         GL_INVALID_VALUE,
         "glDisableVertexAttribArray", "index out of range");
   }
 }
 
 void GLES2DecoderImpl::DoDiscardFramebufferEXT(GLenum target,
                                                GLsizei numAttachments,
                                                const GLenum* attachments) {
+  if (workarounds().disable_fbo_invalidations) {

[vmiura, 2015/03/25 21:43:11]

nit: no need for {} brackets.

[David Yen, 2015/03/25 21:45:27]

Done.

+    return;
+  }
+
   Framebuffer* framebuffer =
       GetFramebufferInfoForTarget(GL_FRAMEBUFFER);
 
   // Validates the attachments. If one of them fails
   // the whole command fails.
   for (GLsizei i = 0; i < numAttachments; ++i) {
     if ((framebuffer &&
         !validators_->attachment.IsValid(attachments[i])) ||
        (!framebuffer &&
         !validators_->backbuffer_attachment.IsValid(attachments[i]))) {
@@ skipping 7926 matching lines @@
   }
 }
 
 // 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