Make nesting/running states a RunLoop rather than a MessageLoop concept.

components/sync/engine_impl/sync_scheduler_impl_unittest.cc

Index: components/sync/engine_impl/sync_scheduler_impl_unittest.cc
diff --git a/components/sync/engine_impl/sync_scheduler_impl_unittest.cc b/components/sync/engine_impl/sync_scheduler_impl_unittest.cc
index d1d45bfeb1e0dd15a85d097bfb26134c92502dc8..151666ff6d32fa9bcba0eeb5c8c1b33f2bd63d3d 100644
--- a/components/sync/engine_impl/sync_scheduler_impl_unittest.cc
+++ b/components/sync/engine_impl/sync_scheduler_impl_unittest.cc
@@ -306,7 +306,7 @@ void RecordSyncShareImpl(SyncShareTimes* times) {
 
 ACTION_P2(RecordSyncShare, times, success) {
   RecordSyncShareImpl(times);
-  if (base::MessageLoop::current()->is_running())
+  if (base::RunLoop::IsRunningOnCurrentThread())
     QuitLoopNow();
   return success;
 }
@@ -315,7 +315,7 @@ ACTION_P3(RecordSyncShareMultiple, times, quit_after, success) {
   RecordSyncShareImpl(times);
   EXPECT_LE(times->size(), quit_after);
   if (times->size() >= quit_after &&
-      base::MessageLoop::current()->is_running()) {
+      base::RunLoop::IsRunningOnCurrentThread()) {
     QuitLoopNow();
   }
   return success;