Revert r11834 because of broken Chromium unit test.

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index c2013e3e38b43b31b43e01ee8fe376dd3eef2d5e..c5e2dc872732be7d1bfb7305d945ef79e11763d2 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -945,12 +945,9 @@ void Isolate::ScheduleThrow(Object* exception) {
   // When scheduling a throw we first throw the exception to get the
   // error reporting if it is uncaught before rescheduling it.
   Throw(exception);
-  PropagatePendingExceptionToExternalTryCatch();
-  if (has_pending_exception()) {
-    thread_local_top()->scheduled_exception_ = pending_exception();
-    thread_local_top()->external_caught_exception_ = false;
-    clear_pending_exception();
-  }
+  thread_local_top()->scheduled_exception_ = pending_exception();
+  thread_local_top()->external_caught_exception_ = false;
+  clear_pending_exception();
 }