Remove all uses of "using namespace std"

content/shell/renderer/test_runner/TestCommon.cpp

 // 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 "content/shell/renderer/test_runner/TestCommon.h"
 
-using namespace std;
-
 namespace content {
 
 namespace {
 
 const char layoutTestsPattern[] = "/LayoutTests/";
-const string::size_type layoutTestsPatternSize = sizeof(layoutTestsPattern) - 1;
+const std::string::size_type layoutTestsPatternSize = sizeof(layoutTestsPattern) - 1;
 const char fileUrlPattern[] = "file:/";
 const char fileTestPrefix[] = "(file test):";
 const char dataUrlPattern[] = "data:";
-const string::size_type dataUrlPatternSize = sizeof(dataUrlPattern) - 1;
+const std::string::size_type dataUrlPatternSize = sizeof(dataUrlPattern) - 1;
 
 }  // namespace
 
-string normalizeLayoutTestURL(const string& url)
+std::string normalizeLayoutTestURL(const std::string& url)
 {
-    string result = url;
+    std::string result = url;
     size_t pos;
-    if (!url.find(fileUrlPattern) && ((pos = url.find(layoutTestsPattern)) != string::npos)) {
+    if (!url.find(fileUrlPattern) && ((pos = url.find(layoutTestsPattern)) != std::string::npos)) {
         // adjust file URLs to match upstream results.
         result.replace(0, pos + layoutTestsPatternSize, fileTestPrefix);
     } else if (!url.find(dataUrlPattern)) {
         // URL-escape data URLs to match results upstream.
-        string path = url.substr(dataUrlPatternSize);
+        std::string path = url.substr(dataUrlPatternSize);
         result.replace(dataUrlPatternSize, url.length(), path);
     }
     return result;
 }
 
 }  // namespace content