Use MakeWeak() to clean up function pointers in NativeHandler.

chrome/renderer/extensions/native_handler.cc

 // 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.
 
 #include "chrome/renderer/extensions/native_handler.h"
 
 #include "base/memory/linked_ptr.h"
 #include "base/logging.h"
 #include "chrome/renderer/extensions/module_system.h"
 #include "v8/include/v8.h"
@@ skipping 20 matching lines @@
   // HandlerFunction below point to freed memory.
   if (!ModuleSystem::IsPresentInCurrentContext()) {
     return v8::ThrowException(v8::Exception::Error(
         v8::String::New("ModuleSystem has been deleted")));
   }
   HandlerFunction* handler_function = static_cast<HandlerFunction*>(
       args.Data().As<v8::External>()->Value());
   return handler_function->Run(args);
 }
 
+// static
+void NativeHandler::DisposeFunction(v8::Persistent<v8::Value> object,
+                                    void* parameter) {
+  HandlerFunction* handler_function =
+      reinterpret_cast<HandlerFunction*>(parameter);
+
+  object.Dispose();
+  delete handler_function;
+}
+
 void NativeHandler::RouteFunction(const std::string& name,
     const HandlerFunction& handler_function) {
-  linked_ptr<HandlerFunction> function(new HandlerFunction(handler_function));
-  // TODO(koz): Investigate using v8's MakeWeak() function instead of holding
-  // on to these pointers here.
-  handler_functions_.push_back(function);
+  HandlerFunction* function = new HandlerFunction(handler_function);
+  // Deleted in DisposeFunction once v8 garbage collects function_template.
+  v8::Persistent<v8::External> function_value =
+      v8::Persistent<v8::External>::New(v8::External::New(function));
+  function_value.MakeWeak(function, DisposeFunction);
   v8::Handle<v8::FunctionTemplate> function_template =
-      v8::FunctionTemplate::New(Router,
-          v8::External::New(function.get()));
+      v8::FunctionTemplate::New(Router, function_value);
   object_template_->Set(name.c_str(), function_template);
 }
 
 void NativeHandler::RouteStaticFunction(const std::string& name,
                                         const HandlerFunc handler_func) {
   v8::Handle<v8::FunctionTemplate> function_template =
       v8::FunctionTemplate::New(handler_func, v8::External::New(this));
   object_template_->Set(name.c_str(), function_template);
 }
 
 }   // extensions