Reduce boilerplace for common pattern to return MaybeHandle.

src/runtime/runtime-forin.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/elements.h"
 #include "src/factory.h"
 #include "src/isolate-inl.h"
@@ skipping 89 matching lines @@
   return HasEnumerableProperty(isolate, receiver, key);
 }
 
 }  // namespace
 
 
 RUNTIME_FUNCTION(Runtime_ForInEnumerate) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0);
-  Handle<HeapObject> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Enumerate(receiver));
-  return *result;
+  RETURN_RESULT_OR_FAILURE(isolate, Enumerate(receiver));
 }
 
 
 RUNTIME_FUNCTION_RETURN_TRIPLE(Runtime_ForInPrepare) {
   HandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   Handle<JSReceiver> receiver = args.at<JSReceiver>(0);
   Handle<Object> cache_type;
   if (!Enumerate(receiver).ToHandle(&cache_type)) {
     return MakeTriple(isolate->heap()->exception(), nullptr, nullptr);
@@ skipping 29 matching lines @@
   DCHECK_LE(index, length);
   return isolate->heap()->ToBoolean(index == length);
 }
 
 
 RUNTIME_FUNCTION(Runtime_ForInFilter) {
   HandleScope scope(isolate);
   DCHECK_EQ(2, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0);
   CONVERT_ARG_HANDLE_CHECKED(Object, key, 1);
-  Handle<Object> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Filter(receiver, key));
-  return *result;
+  RETURN_RESULT_OR_FAILURE(isolate, Filter(receiver, key));
 }
 
 
 RUNTIME_FUNCTION(Runtime_ForInNext) {
   HandleScope scope(isolate);
   DCHECK_EQ(4, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSReceiver, receiver, 0);
   CONVERT_ARG_HANDLE_CHECKED(FixedArray, cache_array, 1);
   CONVERT_ARG_HANDLE_CHECKED(Object, cache_type, 2);
   CONVERT_SMI_ARG_CHECKED(index, 3);
   Handle<Object> key = handle(cache_array->get(index), isolate);
   // Don't need filtering if expected map still matches that of the receiver.
   if (receiver->map() == *cache_type) {
     return *key;
   }
-  Handle<Object> result;
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, result, Filter(receiver, key));
-  return *result;
+  RETURN_RESULT_OR_FAILURE(isolate, Filter(receiver, key));
 }
 
 
 RUNTIME_FUNCTION(Runtime_ForInStep) {
   SealHandleScope scope(isolate);
   DCHECK_EQ(1, args.length());
   CONVERT_SMI_ARG_CHECKED(index, 0);
   DCHECK_LE(0, index);
   DCHECK_LT(index, Smi::kMaxValue);
   return Smi::FromInt(index + 1);
 }
 
 }  // namespace internal
 }  // namespace v8