Introduce MaybeHandle to police exception checking in handlified code.

src/runtime.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3220 matching lines @@
   Vector< Handle<Object> > argv = HandleVector<Object>(NULL, 0);
   Handle<Object> error = isolate->factory()->NewError(message, argv);
   return isolate->Throw(*error);
 }
 
 
 RUNTIME_FUNCTION(MaybeObject*, Runtime_ObjectFreeze) {
   HandleScope scope(isolate);
   ASSERT(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSObject, object, 0);
-  Handle<Object> result = JSObject::Freeze(object);
-  RETURN_IF_EMPTY_HANDLE(isolate, result);
+  Handle<Object> result;
+  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, JSObject::Freeze(object));
   return *result;
 }
 
 
 MUST_USE_RESULT static MaybeObject* CharFromCode(Isolate* isolate,
                                                  Object* char_code) {
   if (char_code->IsNumber()) {
     return isolate->heap()->LookupSingleCharacterStringFromCode(
         NumberToUint32(char_code) & 0xffff);
   }
@@ skipping 11978 matching lines @@
   }
 }
 
 
 void Runtime::OutOfMemory() {
   Heap::FatalProcessOutOfMemory("CALL_AND_RETRY_LAST", true);
   UNREACHABLE();
 }
 
 } }  // namespace v8::internal