[Chrome OS ECHO]: Rename API and method names

chrome/browser/chromeos/extensions/echo_private_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 "chrome/browser/extensions/extension_apitest.h"
 
-class ExtensionOffersPrivateApiTest : public ExtensionApiTest {
+class ExtensionEchoPrivateApiTest : public ExtensionApiTest {
 };
 
-IN_PROC_BROWSER_TEST_F(ExtensionOffersPrivateApiTest, OffersTest) {
-  EXPECT_TRUE(RunComponentExtensionTest("offers/component_extension"))
+IN_PROC_BROWSER_TEST_F(ExtensionEchoPrivateApiTest, EchoTest) {
+  EXPECT_TRUE(RunComponentExtensionTest("echo/component_extension"))
       << message_;
 }