clang/win: Let remaining chromium_code targets build with -Wextra.

chrome/browser/password_manager/password_manager_util_win.cc

Index: chrome/browser/password_manager/password_manager_util_win.cc
diff --git a/chrome/browser/password_manager/password_manager_util_win.cc b/chrome/browser/password_manager/password_manager_util_win.cc
index b05678064b14aa10b7025ce2c31f436f6f1292ce..cc5371f0afddc7a93ac3e697115d97d11c189cc8 100644
--- a/chrome/browser/password_manager/password_manager_util_win.cc
+++ b/chrome/browser/password_manager/password_manager_util_win.cc
@@ -235,7 +235,7 @@ bool AuthenticateUser(gfx::NativeWindow window) {
   base::string16 password_prompt =
       l10n_util::GetStringUTF16(IDS_PASSWORDS_PAGE_AUTHENTICATION_PROMPT);
   HANDLE handle = INVALID_HANDLE_VALUE;
-  int tries = 0;
+  size_t tries = 0;
   bool use_displayname = false;
   bool use_principalname = false;
   DWORD logon_result = 0;