Use the current title for items created by same document navigations.

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 833 matching lines @@
   // Expect at least one more TitleWasSet callback after changing title via
   // JavaScript. On iOS 10 WKWebView fires 3 callbacks after JS excucution
   // with the following title changes: "Title2", "" and "Title2".
   // TODO(crbug.com/696104): There should be only 2 calls of TitleWasSet.
   // Fix expecteation when WKWebView stops sending extra KVO calls.
   ExecuteJavaScript(@"window.document.title = 'Title2';");
   EXPECT_EQ("Title2", base::UTF16ToUTF8(web_state()->GetTitle()));
   EXPECT_GE(observer.title_change_count(), 2);
 };
 
+// Tests that fragment change navigations use title from the previous page.
+TEST_F(CRWWebControllerTitleTest, FragmentChangeNavigationsUsePreviousTitle) {
+  LoadHtml(@"<title>Title1</title>");
+  ASSERT_EQ("Title1", base::UTF16ToUTF8(web_state()->GetTitle()));
+  ExecuteJavaScript(@"window.location.hash = '#1'");
+  EXPECT_EQ("Title1", base::UTF16ToUTF8(web_state()->GetTitle()));
+}
+
 // Test fixture for JavaScript execution.
 class ScriptExecutionTest : public web::WebTestWithWebController {
  protected:
   // Calls |executeUserJavaScript:completionHandler:|, waits for script
   // execution completion, and synchronously returns the result.
   id ExecuteUserJavaScript(NSString* java_script, NSError** error) {
     __block id script_result = nil;
     __block NSError* script_error = nil;
     __block bool script_executed = false;
     [web_controller()
@@ skipping 75 matching lines @@
   web::TestWebStateObserver* observer_ptr = &observer;
   web::SimulateWKWebViewCrash(webView_);
   base::test::ios::WaitUntilCondition(^bool() {
     return observer_ptr->render_process_gone_info();
   });
   EXPECT_EQ(web_state(), observer.render_process_gone_info()->web_state);
   EXPECT_FALSE([web_controller() isViewAlive]);
 };
 
 }  // namespace