gpu: Workaround Adreno 420 bug with deleting current FBO.

gpu/command_buffer/service/framebuffer_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/framebuffer_manager.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "gpu/command_buffer/common/gles2_cmd_utils.h"
 #include "gpu/command_buffer/service/renderbuffer_manager.h"
 #include "gpu/command_buffer/service/texture_manager.h"
@@ skipping 613 matching lines @@
 }
 
 void FramebufferManager::RemoveFramebuffer(GLuint client_id) {
   FramebufferMap::iterator it = framebuffers_.find(client_id);
   if (it != framebuffers_.end()) {
     it->second->MarkAsDeleted();
     framebuffers_.erase(it);
   }
 }
 
+void Framebuffer::UnbindAttachments(GLenum target) {
+  // Replace all attachments with the default Renderbuffer.
+  for (AttachmentMap::const_iterator it = attachments_.begin();
+       it != attachments_.end(); ++it) {
+    AttachRenderbuffer(it->first, NULL);

[vmiura, 2015/02/17 21:48:48]

Hmm, I'm getting some GL errors after doing this so this is probably not the
right thing to do.

+    glFramebufferRenderbufferEXT(target, it->first, GL_RENDERBUFFER, 0);
+  }
+}
+
 void Framebuffer::AttachRenderbuffer(
     GLenum attachment, Renderbuffer* renderbuffer) {
   const Attachment* a = GetAttachment(attachment);
   if (a)
     a->DetachFromFramebuffer(this);
   if (renderbuffer) {
     attachments_[attachment] = scoped_refptr<Attachment>(
         new RenderbufferAttachment(renderbuffer));
   } else {
     attachments_.erase(attachment);
@@ skipping 89 matching lines @@
        ++it) {
     TextureDetachObserver* observer = *it;
     observer->OnTextureRefDetachedFromFramebuffer(texture);
   }
 }
 
 }  // namespace gles2
 }  // namespace gpu