[runtime] Initialize value before calling CallPrinter

NOTREECHECKS=true

Bug: 
Change-Id: I6c4d76be9f032d1149a5128c90995b7302c9d9b5
Reviewed-on: https://chromium-review.googlesource.com/574697
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46724}

src/runtime/runtime-internal.cc

@@ -424,7 +424,7 @@ void UpdateIteratorTemplate(CallPrinter::IteratorHint hint,
 
 MaybeHandle<Object> Runtime::ThrowIteratorError(Isolate* isolate,
                                                 Handle<Object> object) {
-  CallPrinter::IteratorHint hint;
+  CallPrinter::IteratorHint hint = CallPrinter::kNone;
   Handle<String> callsite = RenderCallSite(isolate, object, &hint);
   MessageTemplate::Template id = MessageTemplate::kNonObjectPropertyLoad;
 
@@ -442,7 +442,7 @@ RUNTIME_FUNCTION(Runtime_ThrowCalledNonCallable) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_ARG_HANDLE_CHECKED(Object, object, 0);
-  CallPrinter::IteratorHint hint;
+  CallPrinter::IteratorHint hint = CallPrinter::kNone;
   Handle<String> callsite = RenderCallSite(isolate, object, &hint);
   MessageTemplate::Template id = MessageTemplate::kCalledNonCallable;
   UpdateIteratorTemplate(hint, &id);
@@ -461,7 +461,7 @@ RUNTIME_FUNCTION(Runtime_ThrowConstructedNonConstructable) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_ARG_HANDLE_CHECKED(Object, object, 0);
-  CallPrinter::IteratorHint hint;
+  CallPrinter::IteratorHint hint = CallPrinter::kNone;
   Handle<String> callsite = RenderCallSite(isolate, object, &hint);
   MessageTemplate::Template id = MessageTemplate::kNotConstructor;
   THROW_NEW_ERROR_RETURN_FAILURE(isolate, NewTypeError(id, callsite));