Use base::StartWith() in more places when appropriate.

chrome/browser/chromeos/policy/blocking_login_browsertest.cc

Index: chrome/browser/chromeos/policy/blocking_login_browsertest.cc
diff --git a/chrome/browser/chromeos/policy/blocking_login_browsertest.cc b/chrome/browser/chromeos/policy/blocking_login_browsertest.cc
index 32e622ab61edab86e9465d02ef47c58ee9bfd705..fc0df0d9525a05ec10bc691041e384096f253c7b 100644
--- a/chrome/browser/chromeos/policy/blocking_login_browsertest.cc
+++ b/chrome/browser/chromeos/policy/blocking_login_browsertest.cc
@@ -10,6 +10,7 @@
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/stl_util.h"
+#include "base/strings/string_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/chromeos/login/existing_user_controller.h"
@@ -177,8 +178,10 @@ class BlockingLoginTest
     GaiaUrls* gaia = GaiaUrls::GetInstance();
     if (request.relative_url == gaia->client_login_to_oauth2_url().path() ||
         request.relative_url == gaia->oauth2_token_url().path() ||
-        request.relative_url.find(kDMRegisterRequest) == 0 ||
-        request.relative_url.find(kDMPolicyRequest) == 0) {
+        base::StartsWith(request.relative_url, kDMRegisterRequest,
+                         base::CompareCase::SENSITIVE) ||
+        base::StartsWith(request.relative_url, kDMPolicyRequest,
+                         base::CompareCase::SENSITIVE)) {
       if (!responses_.empty()) {
         response.reset(responses_.back());
         responses_.pop_back();