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

chrome/browser/extensions/content_script_apitest.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 "base/file_util.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/extensions/api/permissions/permissions_api.h"
 #include "chrome/browser/extensions/extension_apitest.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
 #include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/test/base/ui_test_utils.h"
@@ skipping 152 matching lines @@
   PermissionsRequestFunction::SetAutoConfirmForTests(true);
   host_resolver()->AddRule("*.com", "127.0.0.1");
   ASSERT_TRUE(StartTestServer());
   ASSERT_TRUE(RunExtensionTest("content_scripts/permissions")) << message_;
 }
 
 IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptBypassPageCSP) {
   ASSERT_TRUE(StartTestServer());
   ASSERT_TRUE(RunExtensionTest("content_scripts/bypass_page_csp")) << message_;
 }
+
+IN_PROC_BROWSER_TEST_F(ExtensionApiTest, ContentScriptUpdatei18nMessages) {
+  ASSERT_TRUE(StartTestServer());
+  // Create an Extension whos messages.json file is to be updated.
+  base::FilePath extension_dir;
+  file_util::CreateNewTempDirectory("", &extension_dir);
+  file_util::CopyFile(
+      test_data_dir_.AppendASCII(
+          "content_scripts/message_reload1/manifest.json"),

[Devlin, 2013/02/26 05:57:12]

It's better form to append one thing at a time; i.e.
test_data_dir_.AppendASCII("content_scripts")
              .AppendASCII("message_reload")
              .AppendASCII("manifest.json")

This is because AppendASCII does things other than a literal append, and will
also use OS-specific path preferences (for instance, on Windows, backslashes are
used in paths).

(I realize it doesn't do this elsewhere in this file, but it probably should,
and it is more common practice to do so.)

[Patrick Riordan, 2013/02/27 18:30:16]

Done.

+      extension_dir.AppendASCII("manifest.json"));
+  file_util::CopyFile(
+      test_data_dir_.AppendASCII(
+          "content_scripts/message_reload1/contentscript.js"),
+      extension_dir.AppendASCII("contentscript.js"));
+  file_util::CopyDirectory(
+      test_data_dir_.AppendASCII("content_scripts/message_reload1/_locales"),
+      extension_dir.AppendASCII("_locales"),
+      true);
+
+  const extensions::Extension* extension = LoadExtension(extension_dir);
+
+  ResultCatcher catcher;
+
+  // Test that the messages.json file is loaded and the i18n message is loaded.
+  ui_test_utils::NavigateToURL(
+      browser(), test_server()->GetURL("file/extensions/test_file.html"));
+  EXPECT_TRUE(catcher.GetNextResult());
+
+  string16 title;
+  ui_test_utils::GetCurrentTabTitle(browser(), &title);
+  EXPECT_EQ(std::string("FIRSTMESSAGE"), UTF16ToUTF8(title));
+
+  // Change messages.json file and reload extension.
+  file_util::CopyFile(
+      test_data_dir_.AppendASCII(
+          "content_scripts/message_reload1/messages2.json"),
+      extension_dir.AppendASCII("_locales/en/messages.json"));
+  ReloadExtension(extension->id());
+
+  // Check that the i18n message is also changed.
+  ui_test_utils::NavigateToURL(
+      browser(), test_server()->GetURL("file/extensions/test_file.html"));
+  EXPECT_TRUE(catcher.GetNextResult());
+
+  ui_test_utils::GetCurrentTabTitle(browser(), &title);
+  EXPECT_EQ(std::string("SECONDMESSAGE"), UTF16ToUTF8(title));
+}