Reduce boilerplace for common pattern to return MaybeHandle.

src/runtime/runtime-proxy.cc

 // Copyright 2014 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 28 matching lines @@
       isolate, trap,
       Object::GetMethod(Handle<JSReceiver>::cast(handler), trap_name));
   // 6. If trap is undefined, then
   int const arguments_length = args.length() - 2;
   if (trap->IsUndefined()) {
     // 6.a. Return Call(target, thisArgument, argumentsList).
     ScopedVector<Handle<Object>> argv(arguments_length);
     for (int i = 0; i < arguments_length; ++i) {
       argv[i] = args.at<Object>(i + 1);
     }
-    Handle<Object> result;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, result, Execution::Call(isolate, target, receiver,
-                                         arguments_length, argv.start()));
-    return *result;
+    RETURN_RESULT_OR_FAILURE(
+        isolate, Execution::Call(isolate, target, receiver, arguments_length,
+                                 argv.start()));
   }
   // 7. Let argArray be CreateArrayFromList(argumentsList).
   Handle<JSArray> arg_array = isolate->factory()->NewJSArray(
       FAST_ELEMENTS, arguments_length, arguments_length);
   ElementsAccessor* accessor = arg_array->GetElementsAccessor();
   {
     DisallowHeapAllocation no_gc;
     for (int i = 0; i < arguments_length; i++) {
       accessor->Set(arg_array, i, args[i + 1]);
     }
   }
   // 8. Return Call(trap, handler, «target, thisArgument, argArray»).
-  Handle<Object> trap_result;
   Handle<Object> trap_args[] = {target, receiver, arg_array};
-  ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-      isolate, trap_result,
+  RETURN_RESULT_OR_FAILURE(
+      isolate,
       Execution::Call(isolate, trap, handler, arraysize(trap_args), trap_args));
-  return *trap_result;
 }
 
 
 // 9.5.14 [[Construct]] (argumentsList, newTarget)
 RUNTIME_FUNCTION(Runtime_JSProxyConstruct) {
   HandleScope scope(isolate);
   DCHECK_LE(3, args.length());
   CONVERT_ARG_HANDLE_CHECKED(JSProxy, proxy, args.length() - 2);
   CONVERT_ARG_HANDLE_CHECKED(Object, new_target, args.length() - 1);
   Handle<String> trap_name = isolate->factory()->construct_string();
@@ skipping 17 matching lines @@
   // 6. If trap is undefined, then
   int const arguments_length = args.length() - 3;
   if (trap->IsUndefined()) {
     // 6.a. Assert: target has a [[Construct]] internal method.
     DCHECK(target->IsConstructor());
     // 6.b. Return Construct(target, argumentsList, newTarget).
     ScopedVector<Handle<Object>> argv(arguments_length);
     for (int i = 0; i < arguments_length; ++i) {
       argv[i] = args.at<Object>(i + 1);
     }
-    Handle<Object> result;
-    ASSIGN_RETURN_FAILURE_ON_EXCEPTION(
-        isolate, result, Execution::New(isolate, target, new_target,
-                                        arguments_length, argv.start()));
-    return *result;
+    RETURN_RESULT_OR_FAILURE(
+        isolate, Execution::New(isolate, target, new_target, arguments_length,
+                                argv.start()));
   }
   // 7. Let argArray be CreateArrayFromList(argumentsList).
   Handle<JSArray> arg_array = isolate->factory()->NewJSArray(
       FAST_ELEMENTS, arguments_length, arguments_length);
   ElementsAccessor* accessor = arg_array->GetElementsAccessor();
   {
     DisallowHeapAllocation no_gc;
     for (int i = 0; i < arguments_length; i++) {
       accessor->Set(arg_array, i, args[i + 1]);
     }
@@ skipping 42 matching lines @@
 RUNTIME_FUNCTION(Runtime_JSProxyRevoke) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSProxy, proxy, 0);
   JSProxy::Revoke(proxy);
   return isolate->heap()->undefined_value();
 }
 
 }  // namespace internal
 }  // namespace v8