Don't allow updating tabs to javascript URLs without host

chrome/browser/extensions/extension_function.h

 // Copyright (c) 2009 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_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_H_
 
 #include <string>
 
 #include "base/values.h"
@@ skipping 48 matching lines @@
   void set_has_callback(bool has_callback) { has_callback_ = has_callback; }
   bool has_callback() { return has_callback_; }
 
   // Execute the API. Clients should call set_raw_args() and
   // set_request_id() before calling this method. Derived classes should be
   // ready to return raw_result() and error() before returning from this
   // function.
   virtual void Run() = 0;
 
  protected:
+  // Gets the extension that called this function. This can return NULL for
+  // async functions.
+  Extension* GetExtension() {
+    if (dispatcher())
+      return dispatcher()->GetExtension();
+    else
+      return NULL;
+  }
+
   // The peer to the dispatcher that will service this extension function call.
   scoped_refptr<ExtensionFunctionDispatcher::Peer> peer_;
 
   // Id of this request, used to map the response back to the caller.
   int request_id_;
 
   // The name of this function.
   std::string name_;
 
   // True if the js caller provides a callback function to receive the response
@@ skipping 71 matching lines @@
 
   virtual void Run() {
     SendResponse(RunImpl());
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(SyncExtensionFunction);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_FUNCTION_H_