Use explicit WebString conversions in LayoutTest related files

components/test_runner/mock_grammar_check.cc

 // Copyright 2013 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 "components/test_runner/mock_grammar_check.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/macros.h"
 #include "components/test_runner/test_common.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/web/WebTextCheckingResult.h"
 
 namespace test_runner {
 
 bool MockGrammarCheck::CheckGrammarOfString(
     const blink::WebString& text,
     std::vector<blink::WebTextCheckingResult>* results) {
   DCHECK(results);
-  base::string16 string_text = text;
+  base::string16 string_text = text.utf16();
   if (std::find_if(string_text.begin(), string_text.end(), IsASCIIAlpha) ==
       string_text.end())
     return true;
 
   // Find matching grammatical errors from known ones. This function has to
   // check all errors because the given text may consist of two or more
   // sentences that have grammatical errors.
   static const struct {
     const char* text;
     int location;
@@ skipping 22 matching lines @@
           blink::WebTextCheckingResult(blink::WebTextDecorationTypeGrammar,
                                        offset + kGrammarErrors[i].location,
                                        kGrammarErrors[i].length));
       offset += kGrammarErrors[i].length;
     }
   }
   return false;
 }
 
 }  // namespace test_runner