Remove threading from RendererGpuVideoAcceleratorFactories

media/base/bind_to_loop.h.pump

 $$ This is a pump file for generating file templates.  Pump is a python
 $$ script that is part of the Google Test suite of utilities.  Description
 $$ can be found here:
 $$
 $$ http://code.google.com/p/googletest/wiki/PumpManual
 $$
 
 $$ See comment for MAX_ARITY in base/bind.h.pump.
 $var MAX_ARITY = 7
 
 // 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.
 
 #ifndef MEDIA_BASE_BIND_TO_LOOP_H_
 #define MEDIA_BASE_BIND_TO_LOOP_H_
 
 #include "base/bind.h"
 #include "base/location.h"
 #include "base/message_loop/message_loop_proxy.h"
+#include "base/synchronization/waitable_event.h"
 
 // This is a helper utility for base::Bind()ing callbacks on to particular
 // MessageLoops.  A typical use is when |a| (of class |A|) wants to hand a
 // callback such as base::Bind(&A::AMethod, a) to |b|, but needs to ensure that
 // when |b| executes the callback, it does so on a particular MessageLoop.
 //
 // Typical usage: request to be called back on the current thread:
 // other->StartAsyncProcessAndCallMeBack(
 //    media::BindToLoop(MessageLoopProxy::current(),
 //                      base::Bind(&MyClass::MyMethod, this)));
 //
-// Note that like base::Bind(), BindToLoop() can't bind non-constant references,
-// and that *unlike* base::Bind(), BindToLoop() makes copies of its arguments,
-// and thus can't be used with arrays.
+// For synchronous usage, where the callback needs to be executed on another
+// MessageLoop, but the calling thread should block until the callback has been
+// completed, there is BindToLoopSync(), as below:
+//
+// Typical usage: make a request to another thread, and wait for it:
+// do_something_callback =
+//   media::BindToLoopSync(other_message_loop, &OtherClass::DoRequest, other);
+// // ...
+// do_something_callback.Run();  // will block until completion
+//
+// Note that like base::Bind(), BindToLoop() and BindToLoopSync() can't bind
+// non-constant references, and that *unlike* base::Bind(), BindToLoop*() makes
+// copies of its arguments, and thus can't be used with arrays.
 
 namespace media {
 
 // Mimic base::internal::CallbackForward, replacing p.Pass() with
 // base::Passed(&p) to account for the extra layer of indirection.
 namespace internal {
 template <typename T>
 T& TrampolineForward(T& t) { return t; }
 
 template <typename T>
 base::internal::PassedWrapper<scoped_ptr<T> > TrampolineForward(
     scoped_ptr<T>& p) { return base::Passed(&p); }
 
 template <typename T, typename R>
 base::internal::PassedWrapper<scoped_ptr_malloc<T, R> > TrampolineForward(
     scoped_ptr_malloc<T, R>& p) { return base::Passed(&p); }
 
 template <typename T>
 base::internal::PassedWrapper<ScopedVector<T> > TrampolineForward(
     ScopedVector<T>& p) { return base::Passed(&p); }
 
 template <typename T> struct TrampolineHelper;
 
+// Caller helper to call a base::Closure synchronously
+void TrampolineSyncCaller(const base::Closure& closure,
+                          base::WaitableEvent* waiter);
+
 $range ARITY 0..MAX_ARITY
 $for ARITY [[
 $range ARG 1..ARITY
 
 template <$for ARG , [[typename A$(ARG)]]>
 struct TrampolineHelper<void($for ARG , [[A$(ARG)]])> {
   static void Run(
       const scoped_refptr<base::MessageLoopProxy>& loop,
       const base::Callback<void($for ARG , [[A$(ARG)]])>& cb
 $if ARITY != 0 [[, ]]
 $for ARG , [[A$(ARG) a$(ARG)]]
 ) {
     loop->PostTask(FROM_HERE, base::Bind(cb
 $if ARITY != 0 [[, ]]
 $for ARG , [[internal::TrampolineForward(a$(ARG))]]));
   }
+  static void RunSync(
+      const scoped_refptr<base::MessageLoopProxy>& loop,
+      const base::Callback<void($for ARG , [[A$(ARG)]])>& cb
+$if ARITY != 0 [[, ]]
+$for ARG , [[A$(ARG) a$(ARG)]]
+) {
+    DCHECK(!loop->BelongsToCurrentThread());
+    base::WaitableEvent waiter(false, false);
+    loop->PostTask(
+        FROM_HERE,
+        base::Bind(
+            &TrampolineSyncCaller,
+            base::Bind(cb
+$if ARITY != 0 [[, ]]
+$for ARG , [[internal::TrampolineForward(a$(ARG))]]),
+            &waiter));
+    waiter.Wait();
+  }
 };
 
 
 ]]  $$ for ARITY
 
 }  // namespace internal
 
 template<typename T>
 static base::Callback<T> BindToLoop(
     const scoped_refptr<base::MessageLoopProxy>& loop,
     const base::Callback<T>& cb) {
   return base::Bind(&internal::TrampolineHelper<T>::Run, loop, cb);
 }
 
 template<typename T>
+static base::Callback<T> BindToLoopSync(
+    const scoped_refptr<base::MessageLoopProxy>& loop,
+    const base::Callback<T>& cb) {
+  return base::Bind(&internal::TrampolineHelper<T>::RunSync, loop, cb);
+}
+
+template<typename T>
 static base::Callback<T> BindToCurrentLoop(
     const base::Callback<T>& cb) {
   return BindToLoop(base::MessageLoopProxy::current(), cb);
 }
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_BIND_TO_LOOP_H_