Add base:: to string16s in chrome/.

chrome/installer/gcapi/gcapi_last_run_test.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 <limits>
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/guid.h"
 #include "base/strings/string_number_conversions.h"
@@ skipping 37 matching lines @@
                       clients_path.c_str(),
                       KEY_CREATE_SUB_KEY | KEY_SET_VALUE);
     ASSERT_TRUE(client_key.Valid());
     client_key.WriteValue(L"pv", L"1.2.3.4");
   }
 
   bool SetLastRunTime(int64 last_run_time) {
     return SetLastRunTimeString(base::Int64ToString16(last_run_time));
   }
 
-  bool SetLastRunTimeString(const string16& last_run_time_string) {
+  bool SetLastRunTimeString(const base::string16& last_run_time_string) {
     const wchar_t* base_path = google_update::kRegPathClientState;
     std::wstring path(base_path);
     path += L"\\";
     path += google_update::kChromeUpgradeCode;
 
     RegKey client_state(HKEY_CURRENT_USER, path.c_str(), KEY_SET_VALUE);
     return (client_state.Valid() &&
             client_state.WriteValue(
                 google_update::kRegLastRunTimeField,
                 last_run_time_string.c_str()) == ERROR_SUCCESS);
@@ skipping 22 matching lines @@
   EXPECT_EQ(-1, days_since_last_run);
 }
 
 TEST_F(GCAPILastRunTest, OutOfRangeLastRun) {
   Time last_run = Time::NowFromSystemTime() - TimeDelta::FromDays(-42);
   EXPECT_TRUE(SetLastRunTime(last_run.ToInternalValue()));
 
   int days_since_last_run = GoogleChromeDaysSinceLastRun();
   EXPECT_EQ(-1, days_since_last_run);
 }