Use string for Histogram names since these are all ASCII anyway wide-characte...

chrome/renderer/user_script_slave.cc

 // Copyright (c) 2009 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/renderer/user_script_slave.h"
 
 #include "base/histogram.h"
 #include "base/logging.h"
 #include "base/perftimer.h"
 #include "base/pickle.h"
@@ skipping 94 matching lines @@
       inject.append(script_contents_[*script].as_string());
       inject.append(kUserScriptTail);
       frame->ExecuteJavaScript(inject,
                                GURL((*script)->url().spec()),
                                -user_script_start_line_);
       ++num_matched;
     }
   }
 
   if (location == UserScript::DOCUMENT_START) {
-    HISTOGRAM_COUNTS_100(L"UserScripts:DocStart:Count", num_matched);
-    HISTOGRAM_TIMES(L"UserScripts:DocStart:Time", timer.Elapsed());
+    HISTOGRAM_COUNTS_100("UserScripts:DocStart:Count", num_matched);
+    HISTOGRAM_TIMES("UserScripts:DocStart:Time", timer.Elapsed());
   } else {
-    HISTOGRAM_COUNTS_100(L"UserScripts:DocEnd:Count", num_matched);
-    HISTOGRAM_TIMES(L"UserScripts:DocEnd:Time", timer.Elapsed());
+    HISTOGRAM_COUNTS_100("UserScripts:DocEnd:Count", num_matched);
+    HISTOGRAM_TIMES("UserScripts:DocEnd:Time", timer.Elapsed());
   }
 
   return true;
 }