Fixed and reenabled the flaky test "WebViewAPITest.TestAutosizeAfterNavigation".

extensions/browser/guest_view/web_view/web_view_apitest.cc

 // Copyright 2014 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 "extensions/browser/guest_view/web_view/web_view_apitest.h"
 
 #include "base/command_line.h"
 #include "base/path_service.h"
 #include "base/strings/string_util.h"
 #include "base/strings/stringprintf.h"
@@ skipping 372 matching lines @@
 }
 
 IN_PROC_BROWSER_TEST_F(WebViewAPITest, TestAPIMethodExistence) {
   RunTest("testAPIMethodExistence", "web_view/apitest");
 }
 
 IN_PROC_BROWSER_TEST_F(WebViewAPITest, TestAssignSrcAfterCrash) {
   RunTest("testAssignSrcAfterCrash", "web_view/apitest");
 }
 
-IN_PROC_BROWSER_TEST_F(WebViewAPITest, DISABLED_TestAutosizeAfterNavigation) {
+IN_PROC_BROWSER_TEST_F(WebViewAPITest, TestAutosizeAfterNavigation) {
   RunTest("testAutosizeAfterNavigation", "web_view/apitest");
 }
 
 IN_PROC_BROWSER_TEST_F(WebViewAPITest, TestAutosizeBeforeNavigation) {
   RunTest("testAutosizeBeforeNavigation", "web_view/apitest");
 }
 
 IN_PROC_BROWSER_TEST_F(WebViewDPIAPITest, TestAutosizeBeforeNavigation) {
   RunTest("testAutosizeBeforeNavigation", "web_view/apitest");
 }
@@ skipping 302 matching lines @@
   RunTest("testWebRequestAPIGoogleProperty", "web_view/apitest");
 }
 
 // This test verifies that webview.contentWindow works inside an iframe
 IN_PROC_BROWSER_TEST_F(WebViewAPITest, TestWebViewInsideFrame) {
   LaunchApp("web_view/inside_iframe");
 }
 
 
 }  // namespace extensions