Replace MessageLoopProxy with ThreadTaskRunnerHandle in src/sync/.

sync/internal_api/sync_context_proxy_impl.cc

Index: sync/internal_api/sync_context_proxy_impl.cc
diff --git a/sync/internal_api/sync_context_proxy_impl.cc b/sync/internal_api/sync_context_proxy_impl.cc
index 91edfbe7880e0d98f9c61944b4eb134159667efe..9e8db1cf1d1f4130ebf089f7f7496d759179903e 100644
--- a/sync/internal_api/sync_context_proxy_impl.cc
+++ b/sync/internal_api/sync_context_proxy_impl.cc
@@ -6,7 +6,8 @@
 
 #include "base/bind.h"
 #include "base/location.h"
-#include "base/message_loop/message_loop_proxy.h"
+#include "base/single_thread_task_runner.h"
+#include "base/thread_task_runner_handle.h"
 #include "sync/engine/non_blocking_sync_common.h"
 #include "sync/internal_api/public/sync_context.h"
 
@@ -31,7 +32,7 @@ void SyncContextProxyImpl::ConnectTypeToSync(
                                          sync_context_,
                                          type,
                                          data_type_state,
-                                         base::MessageLoopProxy::current(),
+                                         base::ThreadTaskRunnerHandle::Get(),
                                          type_sync_proxy));
 }