Delete the extensions i18n message map when extension unload is received.

chrome/renderer/extensions/dispatcher.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/dispatcher.h"
 
 #include "base/callback.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/string_piece.h"
 #include "chrome/common/child_process_logging.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/chrome_version_info.h"
 #include "chrome/common/extensions/api/extension_api.h"
 #include "chrome/common/extensions/background_info.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_messages.h"
 #include "chrome/common/extensions/manifest.h"
+#include "chrome/common/extensions/message_bundle.h"
 #include "chrome/common/extensions/permissions/permission_set.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/common/view_type.h"
 #include "chrome/renderer/chrome_render_process_observer.h"
 #include "chrome/renderer/extensions/api_definitions_natives.h"
 #include "chrome/renderer/extensions/app_bindings.h"
 #include "chrome/renderer/extensions/app_runtime_custom_bindings.h"
 #include "chrome/renderer/extensions/app_window_custom_bindings.h"
 #include "chrome/renderer/extensions/chrome_v8_context.h"
 #include "chrome/renderer/extensions/chrome_v8_extension.h"
@@ skipping 479 matching lines @@
   extensions_.Remove(id);
   active_extension_ids_.erase(id);
 
   // If the extension is later reloaded with a different set of permissions,
   // we'd like it to get a new isolated world ID, so that it can pick up the
   // changed origin whitelist.
   user_script_slave_->RemoveIsolatedWorld(id);
 
   v8_context_set_.OnExtensionUnloaded(id);
 
+  // Invalidates the messages map for the extension in case the extension is

[Yoyo Zhou, 2013/03/08 22:17:50]

By the way, the CL description is way too verbose and doesn't get to the point.
You don't need to explain caches from scratch; you can assume the reader has a
basic understanding of Chromium. You can replace lines 2-5 with this, basically,
and include the word "cache" after "message map" in the first line.

Also, it improves readability to put a newline after line 1.

[Patrick Riordan, 2013/03/11 17:32:42]

Done.

+  // reloaded with a new messages map.
+  EraseL10nMessagesMap(id);
+
   // We don't do anything with existing platform-app stylesheets. They will
   // stay resident, but the URL pattern corresponding to the unloaded
   // extension's URL just won't match anything anymore.
 }
 
 void Dispatcher::OnSetScriptingWhitelist(
     const Extension::ScriptingWhitelist& extension_ids) {
   Extension::SetScriptingWhitelist(extension_ids);
 }
 
@@ skipping 635 matching lines @@
     std::string error_msg = base::StringPrintf(kMessage, function_name.c_str());
     v8::ThrowException(
         v8::Exception::Error(v8::String::New(error_msg.c_str())));
     return false;
   }
 
   return true;
 }
 
 }  // namespace extensions