Context menu egtests, plus related utilities.

ios/web/public/test/earl_grey/web_view_matchers.h

 // Copyright 2016 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 <string>
+#ifndef IOS_WEB_PUBLIC_TEST_EARL_GREY_WEB_VIEW_MATCHERS_H_
+#define IOS_WEB_PUBLIC_TEST_EARL_GREY_WEB_VIEW_MATCHERS_H_
+
+#include <string>
 
 #import <EarlGrey/EarlGrey.h>
 
 #import "ios/web/public/web_state/web_state.h"
 
 namespace web {
 
 // Matcher for WKWebView which belogs to the given |webState|.
 id<GREYMatcher> webViewInWebState(WebState* web_state);
 
 // Matcher for WKWebView containing |text|.
-id<GREYMatcher> webViewContainingText(std::string text, WebState* web_state);
+id<GREYMatcher> webViewContainingText(const std::string& text,
+                                      WebState* web_state);
 
 // Matcher for WKWebView containing a blocked |image_id|.  When blocked, the
 // image will be smaller than |expected_size|.
-id<GREYMatcher> webViewContainingBlockedImage(std::string image_id,
+id<GREYMatcher> webViewContainingBlockedImage(const std::string& image_id,
                                               CGSize expected_size,
                                               WebState* web_state);
 
 // Matcher for WKWebView containing an html element which matches |selector|.
-id<GREYMatcher> webViewCssSelector(std::string selector, WebState* web_state);
+id<GREYMatcher> webViewCssSelector(const std::string& selector,
+                                   WebState* web_state);
 
 // Matcher for WKWebView's scroll view.
 id<GREYMatcher> webViewScrollView(WebState* web_state);
 
 }  // namespace web
+
+#endif  // IOS_WEB_PUBLIC_TEST_EARL_GREY_WEB_VIEW_MATCHERS_H_