[Cleanup] Remove StringPrintf from global namespace

chrome/common/cloud_print/cloud_print_helpers_unittest.cc

 // 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.
 
 #include "chrome/common/cloud_print/cloud_print_helpers.h"
 
 #include "base/md5.h"
 #include "base/stringprintf.h"
 #include "base/sys_info.h"
 #include "chrome/common/chrome_version_info.h"
@@ skipping 65 matching lines @@
   CheckURLs(GURL("http://www.myprinterserver.com"));
   CheckURLs(GURL("http://www.myprinterserver.com/"));
 }
 
 TEST(CloudPrintHelpersTest, GetHashOfPrinterTags) {
   PrinterTags printer_tags;
   printer_tags["tag1"] = std::string("value1");
   printer_tags["tag2"] = std::string("value2");
 
   chrome::VersionInfo version_info;
-  std::string expected_list_string = StringPrintf(
+  std::string expected_list_string = base::StringPrintf(
       "chrome_version%ssystem_name%ssystem_version%stag1value1tag2value2",
       version_info.CreateVersionString().c_str(),
       base::SysInfo::OperatingSystemName().c_str(),
       base::SysInfo::OperatingSystemVersion().c_str());
   EXPECT_EQ(base::MD5String(expected_list_string),
             GetHashOfPrinterTags(printer_tags));
 }
 
 TEST(CloudPrintHelpersTest, GetPostDataForPrinterTags) {
   PrinterTags printer_tags;
@@ skipping 26 matching lines @@
       std::string("__test__tagshash")));
 }
 
 TEST(CloudPrintHelpersTest, GetCloudPrintAuthHeader) {
   std::string test_auth("testauth");
   EXPECT_EQ("Authorization: OAuth testauth",
             GetCloudPrintAuthHeader(test_auth));
 }
 
 }  // namespace cloud_print