Object::GetElements() and friends maybehandlification.

src/handles.h

 // Copyright 2011 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 269 matching lines @@
   friend class HandleScopeImplementer;
 };
 
 
 // ----------------------------------------------------------------------------
 // Handle operations.
 // They might invoke garbage collection. The result is an handle to
 // an object of expected type, or the handle is an error if running out
 // of space or encountering an internal error.
 
-Handle<Object> GetProperty(Handle<JSReceiver> obj, const char* name);
+MUST_USE_RESULT MaybeHandle<Object> GetProperty(Handle<JSReceiver> obj,
+                                                const char* name);
 
 // Get the JS object corresponding to the given script; create it
 // if none exists.
 Handle<JSValue> GetScriptWrapper(Handle<Script> script);
 
 // Script line number computations. Note that the line number is zero-based.
 void InitScriptLineEnds(Handle<Script> script);
 // For string calculates an array of line end positions. If the string
 // does not end with a new line character, this character may optionally be
 // imagined.
 Handle<FixedArray> CalculateLineEnds(Handle<String> string,
                                      bool with_imaginary_last_new_line);
 int GetScriptLineNumber(Handle<Script> script, int code_position);
 // The safe version does not make heap allocations but may work much slower.
 int GetScriptLineNumberSafe(Handle<Script> script, int code_position);
 int GetScriptColumnNumber(Handle<Script> script, int code_position);
 Handle<Object> GetScriptNameOrSourceURL(Handle<Script> script);
 
 // Computes the enumerable keys from interceptors. Used for debug mirrors and
 // by GetKeysInFixedArrayFor below.
 v8::Handle<v8::Array> GetKeysForNamedInterceptor(Handle<JSReceiver> receiver,
                                                  Handle<JSObject> object);
 v8::Handle<v8::Array> GetKeysForIndexedInterceptor(Handle<JSReceiver> receiver,
                                                    Handle<JSObject> object);
 
 enum KeyCollectionType { LOCAL_ONLY, INCLUDE_PROTOS };
 
 // Computes the enumerable keys for a JSObject. Used for implementing
 // "for (n in object) { }".
-Handle<FixedArray> GetKeysInFixedArrayFor(Handle<JSReceiver> object,
-                                          KeyCollectionType type,
-                                          bool* threw);
-Handle<JSArray> GetKeysFor(Handle<JSReceiver> object, bool* threw);
+MUST_USE_RESULT MaybeHandle<FixedArray> GetKeysInFixedArrayFor(
+    Handle<JSReceiver> object,
+    KeyCollectionType type);
+MUST_USE_RESULT MaybeHandle<JSArray> GetKeysFor(Handle<JSReceiver> object);
 Handle<FixedArray> ReduceFixedArrayTo(Handle<FixedArray> array, int length);
 Handle<FixedArray> GetEnumPropertyKeys(Handle<JSObject> object,
                                        bool cache_result);
 
 Handle<JSGlobalProxy> ReinitializeJSGlobalProxy(
     Handle<JSFunction> constructor,
     Handle<JSGlobalProxy> global);
 
 void AddWeakObjectToCodeDependency(Heap* heap,
                                    Handle<Object> object,
@@ skipping 23 matching lines @@
 
   void Initialize() {
     next = limit = NULL;
     level = 0;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_HANDLES_H_