Remove some wstrings in test_shell.

webkit/tools/test_shell/test_shell_mac.mm

Index: webkit/tools/test_shell/test_shell_mac.mm
diff --git a/webkit/tools/test_shell/test_shell_mac.mm b/webkit/tools/test_shell/test_shell_mac.mm
index 7c8c5b46c1ddfeb577bf3ae097121b7e5bb6718c..2aa62b0c14ef5d72f23bd32cbdf1a0a1ecc832dd 100644
--- a/webkit/tools/test_shell/test_shell_mac.mm
+++ b/webkit/tools/test_shell/test_shell_mac.mm
@@ -532,7 +532,7 @@ void TestShell::ResizeSubViews() {
 }
 
 void TestShell::LoadURLForFrame(const GURL& url,
-                                const std::wstring& frame_name) {
+                                const string16& frame_name) {
   if (!url.is_valid())
     return;
 
@@ -545,7 +545,7 @@ void TestShell::LoadURLForFrame(const GURL& url,
   }
 
   navigation_controller_->LoadEntry(
-      new TestNavigationEntry(-1, url, std::wstring(), frame_name));
+      new TestNavigationEntry(-1, url, frame_name));
 }
 
 bool TestShell::PromptForSaveFile(const wchar_t* prompt_title,