Fix compile errors on Windows and Mac introduced by r10093.

test/cctest/test-heap.cc

Index: test/cctest/test-heap.cc
diff --git a/test/cctest/test-heap.cc b/test/cctest/test-heap.cc
index 3daf81991d2101126c05c0d2cfcd193608660a54..71f9ac5b3f0c987058b568d30d3ceab2d8cd4c73 100644
--- a/test/cctest/test-heap.cc
+++ b/test/cctest/test-heap.cc
@@ -1313,7 +1313,7 @@ TEST(IdleNotificationAdvancesIncrementalMarking) {
   }
   intptr_t old_size = HEAP->SizeOfObjects();
   bool no_idle_work = v8::V8::IdleNotification();
-  while (!v8::V8::IdleNotification());
+  while (!v8::V8::IdleNotification()) ;
   intptr_t new_size = HEAP->SizeOfObjects();
   CHECK(no_idle_work || new_size < 3 * old_size / 4);
 }