Extensions: pass ChromeV8Context around instead of v8::Handle.

chrome/renderer/extensions/object_backed_native_handler.h

 // Copyright (c) 2012 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_OBJECT_BACKED_NATIVE_HANDLER_H_
 #define CHROME_RENDERER_EXTENSIONS_OBJECT_BACKED_NATIVE_HANDLER_H_
 
 #include <string>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/memory/linked_ptr.h"
 #include "chrome/renderer/extensions/native_handler.h"
 #include "chrome/renderer/extensions/scoped_persistent.h"
 #include "v8/include/v8.h"
 
 namespace extensions {
+class ChromeV8Context;
 
 // An ObjectBackedNativeHandler is a factory for JS objects with functions on
 // them that map to native C++ functions. Subclasses should call RouteFunction()
 // in their constructor to define functions on the created JS objects.
 class ObjectBackedNativeHandler : public NativeHandler {
  public:
-  explicit ObjectBackedNativeHandler(v8::Handle<v8::Context> context);
+  explicit ObjectBackedNativeHandler(ChromeV8Context* context);
   virtual ~ObjectBackedNativeHandler();
 
   // Create an object with bindings to the native functions defined through
   // RouteFunction().
   virtual v8::Handle<v8::Object> NewInstance() OVERRIDE;
 
  protected:
   typedef base::Callback<v8::Handle<v8::Value>(const v8::Arguments&)>
       HandlerFunction;
 
   // Installs a new 'route' from |name| to |handler_function|. This means that
   // NewInstance()s of this ObjectBackedNativeHandler will have a property
   // |name| which will be handled by |handler_function|.
   void RouteFunction(const std::string& name,
                      const HandlerFunction& handler_function);
 
-  v8::Handle<v8::Context> v8_context() { return v8_context_.get(); }
+  v8::Handle<v8::Context> v8_context();

[not at google - send to devlin, 2013/05/29 15:55:13]

can this be made to return a ChromeV8Context* (and call it context()) rather
than the v8_context()? then the context_ below can be private.

[marja, 2013/05/29 16:56:33]

Done.

 
   virtual void Invalidate() OVERRIDE;
 
+ protected:
+  ChromeV8Context* context_;

[not at google - send to devlin, 2013/05/29 15:55:13]

then this can be private

[marja, 2013/05/29 16:56:33]

Done.

+
  private:
   // Callback for RouteFunction which routes the V8 call to the correct
   // base::Bound callback.
   static v8::Handle<v8::Value> Router(const v8::Arguments& args);
 
   // When RouteFunction is called we create a v8::Object to hold the data we
   // need when handling it in Router() - this is the base::Bound function to
   // route to.
   //
   // We need a v8::Object because it's possible for v8 to outlive the
   // base::Bound function; the lifetime of an ObjectBackedNativeHandler is the
   // lifetime of webkit's involvement with it, not the life of the v8 context.
   // A scenario when v8 will outlive us is if a frame holds onto the
   // contentWindow of an iframe after it's removed.
   //
   // So, we use v8::Objects here to hold that data, effectively refcounting
   // the data. When |this| is destroyed we remove the base::Bound function from
   // the object to indicate that it shoudn't be called.
   typedef std::vector<v8::Persistent<v8::Object> > RouterData;
   RouterData router_data_;
 
-  // TODO(kalman): Just pass around a ChromeV8Context. It already has a
-  // persistent handle to this context.
-  ScopedPersistent<v8::Context> v8_context_;
-
   ScopedPersistent<v8::ObjectTemplate> object_template_;
 
   DISALLOW_COPY_AND_ASSIGN(ObjectBackedNativeHandler);
 };
 
 }  // extensions
 
 #endif  // CHROME_RENDERER_EXTENSIONS_OBJECT_BACKED_NATIVE_HANDLER_H_