Remove unsafe access hacks from ScopedPersistent.

chrome/renderer/extensions/scoped_persistent.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_RENDERER_EXTENSIONS_SCOPED_PERSISTENT_H_
 #define CHROME_RENDERER_EXTENSIONS_SCOPED_PERSISTENT_H_
 
 #include "base/logging.h"
 #include "v8/include/v8.h"
 
@@ skipping 22 matching lines @@
       reset();
   }
 
   void reset() {
     if (handle_.IsEmpty())
       return;
     handle_.Dispose();
     handle_.Clear();
   }
 
-  v8::Handle<T> operator->() const {
-    return get();
-  }
-
-  // TODO(dcarney): Remove this function
-  // This is an unsafe access to the underlying handle
-  v8::Handle<T> get() const {
-    return *reinterpret_cast<v8::Handle<T>*>(
-      const_cast<v8::Persistent<T>* >(&handle_));
+  bool IsEmpty() const {
+    return handle_.IsEmpty();
   }
 
   v8::Handle<T> NewHandle() const {
     if (handle_.IsEmpty())
       return v8::Local<T>();
     return v8::Local<T>::New(GetIsolate(handle_), handle_);

[Jeffrey Yasskin, 2013/09/09 17:45:07]

I assume this method is going away soon too?

[marja, 2013/09/09 18:16:18]

v8::Isolate::GetCurrent is going away; ideally we'd always give an isolate here
(and get rid of the GetIsolate funcs below - I'm not quite sure why they exist).

   }
 
+  v8::Handle<T> NewHandle(v8::Isolate* isolate) const {

[Jeffrey Yasskin, 2013/09/09 17:45:07]

I've never quite understood when to use Local vs Handle. I assume you've gotten
this return type right.

[marja, 2013/09/09 18:16:18]

They're basically the same thing - ATM Local is the only subclass of Handle. At
some point those classes will merge (but there's no decision yet if it'll be
called Local or Handle).

+    if (handle_.IsEmpty())
+      return v8::Local<T>();
+    return v8::Local<T>::New(isolate, handle_);
+  }
+
   template<typename P>
   void MakeWeak(P* parameters,
                 typename v8::WeakReferenceCallbacks<T, P>::Revivable callback) {
     handle_.MakeWeak(parameters, callback);
   }
 
  private:
   template <typename U>
   static v8::Isolate* GetIsolate(v8::Handle<U> object_handle) {
     // Only works for v8::Object and its subclasses. Add specialisations for
@@ skipping 13 matching lines @@
   }
 
   v8::Persistent<T> handle_;
 
   DISALLOW_COPY_AND_ASSIGN(ScopedPersistent);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_RENDERER_EXTENSIONS_SCOPED_PERSISTENT_H_