Cleanup: Pass std::string as const reference from content/

content/browser/session_history_browsertest.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/strings/string_util.h"
 #include "base/strings/stringprintf.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
@@ skipping 39 matching lines @@
 
   void SetUpOnMainThread() override {
     ASSERT_TRUE(embedded_test_server()->InitializeAndWaitUntilReady());
     embedded_test_server()->RegisterRequestHandler(
         base::Bind(&HandleEchoTitleRequest, "/echotitle"));
 
     NavigateToURL(shell(), GURL(url::kAboutBlankURL));
   }
 
   // Simulate clicking a link.  Only works on the frames.html testserver page.
-  void ClickLink(std::string node_id) {
+  void ClickLink(const std::string& node_id) {
     GURL url("javascript:clickLink('" + node_id + "')");
     NavigateToURL(shell(), url);
   }
 
   // Simulate filling in form data.  Only works on the frames.html page with
   // subframe = form.html, and on form.html itself.
-  void FillForm(std::string node_id, std::string value) {
+  void FillForm(const std::string& node_id, const std::string& value) {
     GURL url("javascript:fillForm('" + node_id + "', '" + value + "')");
     // This will return immediately, but since the JS executes synchronously
     // on the renderer, it will complete before the next navigate message is
     // processed.
     NavigateToURL(shell(), url);
   }
 
   // Simulate submitting a form.  Only works on the frames.html page with
   // subframe = form.html, and on form.html itself.
-  void SubmitForm(std::string node_id) {
+  void SubmitForm(const std::string& node_id) {
     GURL url("javascript:submitForm('" + node_id + "')");
     NavigateToURL(shell(), url);
   }
 
   // Navigate session history using history.go(distance).
-  void JavascriptGo(std::string distance) {
+  void JavascriptGo(const std::string& distance) {
     GURL url("javascript:history.go('" + distance + "')");
     NavigateToURL(shell(), url);
   }
 
   std::string GetTabTitle() {
     return base::UTF16ToASCII(shell()->web_contents()->GetTitle());
   }
 
   GURL GetTabURL() {
     return shell()->web_contents()->GetLastCommittedURL();
   }
 
-  GURL GetURL(const std::string file) {
+  GURL GetURL(const std::string& file) {
     return embedded_test_server()->GetURL(
         std::string("/session_history/") + file);
   }
 
   void NavigateAndCheckTitle(const char* filename,
                              const std::string& expected_title) {
     base::string16 expected_title16(base::ASCIIToUTF16(expected_title));
     TitleWatcher title_watcher(shell()->web_contents(), expected_title16);
     NavigateToURL(shell(), GetURL(filename));
     ASSERT_EQ(expected_title16, title_watcher.WaitAndGetTitle());
@@ skipping 384 matching lines @@
   NavigateToURL(shell(), GetURL("title2.html"));
 
   ASSERT_TRUE(ExecuteScriptAndExtractInt(
       shell()->web_contents(),
       "domAutomationController.send(history.length)",
       &length));
   EXPECT_EQ(2, length);
 }
 
 }  // namespace content