Reduce boilerplace for common pattern to return MaybeHandle.

src/isolate.h

Index: src/isolate.h
diff --git a/src/isolate.h b/src/isolate.h
index 40f0c0ea5c93e3ae13bacfa9b832273c0e1d0133..da803d6d866defcd8b0453b69faa7a3bbe8283c6 100644
--- a/src/isolate.h
+++ b/src/isolate.h
@@ -124,6 +124,17 @@ typedef ZoneList<Handle<Object> > ZoneObjectList;
 #define RETURN_EXCEPTION_IF_SCHEDULED_EXCEPTION(isolate, T) \
   RETURN_VALUE_IF_SCHEDULED_EXCEPTION(isolate, MaybeHandle<T>())
 
+#define RETURN_RESULT_OR_FAILURE(isolate, call)     \
+  do {                                              \
+    Handle<Object> __result__;                      \
+    Isolate* __isolate__ = (isolate);               \
+    if (!(call).ToHandle(&__result__)) {            \
+      DCHECK(__isolate__->has_pending_exception()); \
+      return __isolate__->heap()->exception();      \
+    }                                               \
+    return *__result__;                             \
+  } while (false)
+
 #define ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, dst, call, value)  \
   do {                                                               \
     if (!(call).ToHandle(&dst)) {                                    \
@@ -132,21 +143,26 @@ typedef ZoneList<Handle<Object> > ZoneObjectList;
     }                                                                \
   } while (false)
 
-#define ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, dst, call)  \
-  ASSIGN_RETURN_ON_EXCEPTION_VALUE(                             \
-      isolate, dst, call, isolate->heap()->exception())
+#define ASSIGN_RETURN_FAILURE_ON_EXCEPTION(isolate, dst, call)          \
+  do {                                                                  \
+    Isolate* __isolate__ = (isolate);                                   \
+    ASSIGN_RETURN_ON_EXCEPTION_VALUE(__isolate__, dst, call,            \
+                                     __isolate__->heap()->exception()); \
+  } while (false)
 
 #define ASSIGN_RETURN_ON_EXCEPTION(isolate, dst, call, T)  \
   ASSIGN_RETURN_ON_EXCEPTION_VALUE(isolate, dst, call, MaybeHandle<T>())
 
-#define THROW_NEW_ERROR(isolate, call, T)               \
-  do {                                                  \
-    return isolate->Throw<T>(isolate->factory()->call); \
+#define THROW_NEW_ERROR(isolate, call, T)                       \
+  do {                                                          \
+    Isolate* __isolate__ = (isolate);                           \
+    return __isolate__->Throw<T>(__isolate__->factory()->call); \
   } while (false)
 
-#define THROW_NEW_ERROR_RETURN_FAILURE(isolate, call) \
-  do {                                                \
-    return isolate->Throw(*isolate->factory()->call); \
+#define THROW_NEW_ERROR_RETURN_FAILURE(isolate, call)         \
+  do {                                                        \
+    Isolate* __isolate__ = (isolate);                         \
+    return __isolate__->Throw(*__isolate__->factory()->call); \
   } while (false)
 
 #define RETURN_ON_EXCEPTION_VALUE(isolate, call, value)            \
@@ -157,8 +173,12 @@ typedef ZoneList<Handle<Object> > ZoneObjectList;
     }                                                              \
   } while (false)
 
-#define RETURN_FAILURE_ON_EXCEPTION(isolate, call)  \
-  RETURN_ON_EXCEPTION_VALUE(isolate, call, isolate->heap()->exception())
+#define RETURN_FAILURE_ON_EXCEPTION(isolate, call)               \
+  do {                                                           \
+    Isolate* __isolate__ = (isolate);                            \
+    RETURN_ON_EXCEPTION_VALUE(__isolate__, call,                 \
+                              __isolate__->heap()->exception()); \
+  } while (false);
 
 #define RETURN_ON_EXCEPTION(isolate, call, T)  \
   RETURN_ON_EXCEPTION_VALUE(isolate, call, MaybeHandle<T>())