Fixed title updating for back forward navigation.

ios/web/web_state/ui/crw_web_controller_unittest.mm

 // Copyright 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.
 
 #import "ios/web/web_state/ui/crw_web_controller.h"
 
 #import <WebKit/WebKit.h>
 
 #include <utility>
 
@@ skipping 760 matching lines @@
   ExecuteJavaScript(@"__gCrWeb['windowId'] = '';");
 
   // Script is not evaluated because of windowID mismatch.
   ExecuteJavaScript(@"window.test2 = '2';");
   EXPECT_FALSE(ExecuteJavaScript(@"window.test2"));
 }
 
 TEST_F(CRWWebControllerTest, WebUrlWithTrustLevel) {
   [[[mockWebView_ stub] andReturn:[NSURL URLWithString:@(kTestURLString)]] URL];
   [[[mockWebView_ stub] andReturnBool:NO] hasOnlySecureContent];
+  [[[mockWebView_ stub] andReturn:@""] title];
 
   // Stub out the injection process.
   [[mockWebView_ stub] evaluateJavaScript:OCMOCK_ANY
                         completionHandler:OCMOCK_ANY];
 
   // Simulate registering load request to avoid failing page load simulation.
   [web_controller() simulateLoadRequestWithURL:GURL(kTestURLString)];
   // Simulate a page load to trigger a URL update.
   [static_cast<id<WKNavigationDelegate>>(web_controller()) webView:mockWebView_
                                                didCommitNavigation:nil];
@@ skipping 263 matching lines @@
   };
 
   RenderProcessGoneObserver observer(web_state());
   web::SimulateWKWebViewCrash(webView_);
   observer.WaitForRenderProcessGone();
 
   EXPECT_FALSE([web_controller() isViewAlive]);
 };
 
 }  // namespace