Add gpu::MailboxHolder to hold state for a gpu::Mailbox

content/browser/aura/owned_mailbox.cc

Index: content/browser/aura/owned_mailbox.cc
diff --git a/content/browser/aura/owned_mailbox.cc b/content/browser/aura/owned_mailbox.cc
index 1a99d335ac245f3760d29c29af9c7ae531eb632b..1a174d324e3d6cbaecc183480646946c3be21717 100644
--- a/content/browser/aura/owned_mailbox.cc
+++ b/content/browser/aura/owned_mailbox.cc
@@ -11,31 +11,30 @@
 namespace content {
 
 OwnedMailbox::OwnedMailbox(GLHelper* gl_helper)
-    : texture_id_(0), sync_point_(0), gl_helper_(gl_helper) {
+    : texture_id_(0), gl_helper_(gl_helper) {
   texture_id_ = gl_helper_->CreateTexture();
-  mailbox_ = gl_helper_->ProduceMailboxFromTexture(texture_id_, &sync_point_);
+  mailbox_holder_ = gl_helper_->ProduceMailboxHolderFromTexture(texture_id_);
   ImageTransportFactory::GetInstance()->AddObserver(this);
 }
 
 OwnedMailbox::~OwnedMailbox() {
   ImageTransportFactory::GetInstance()->RemoveObserver(this);
   if (gl_helper_) {
-    gl_helper_->WaitSyncPoint(sync_point_);
+    gl_helper_->WaitSyncPoint(mailbox_holder_.sync_point);
     gl_helper_->DeleteTexture(texture_id_);
   }
 }
 
 void OwnedMailbox::UpdateSyncPoint(uint32 sync_point) {
   if (sync_point)
-    sync_point_ = sync_point;
+    mailbox_holder_.sync_point = sync_point;
 }
 
 void OwnedMailbox::OnLostResources() {
-  gl_helper_->WaitSyncPoint(sync_point_);
+  gl_helper_->WaitSyncPoint(mailbox_holder_.sync_point);
   gl_helper_->DeleteTexture(texture_id_);
   texture_id_ = 0;
-  mailbox_ = gpu::Mailbox();
-  sync_point_ = 0;
+  mailbox_holder_ = gpu::MailboxHolder();
   gl_helper_ = NULL;
 }