Get rid of FilePath::FromWStringHack from google_chrome_distribution.[cc,h].

chrome/installer/util/google_chrome_distribution_dummy.cc

Index: chrome/installer/util/google_chrome_distribution_dummy.cc
diff --git a/chrome/installer/util/google_chrome_distribution_dummy.cc b/chrome/installer/util/google_chrome_distribution_dummy.cc
index 4d16c687713cf6cd18e7e2b0df1cf2e4ea12a9c9..1b515d96a0102f70d8d6598252d1d27672dc4c66 100644
--- a/chrome/installer/util/google_chrome_distribution_dummy.cc
+++ b/chrome/installer/util/google_chrome_distribution_dummy.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 //
@@ -12,6 +12,7 @@
 
 #include <windows.h>
 
+#include "base/file_path.h"
 #include "base/logging.h"
 
 GoogleChromeDistribution::GoogleChromeDistribution(
@@ -118,7 +119,7 @@ void GoogleChromeDistribution::InactiveUserToastExperiment(int flavor,
 }
 
 bool GoogleChromeDistribution::ExtractUninstallMetricsFromFile(
-    const std::wstring& file_path, std::wstring* uninstall_metrics_string) {
+    const FilePath& file_path, std::wstring* uninstall_metrics_string) {
   NOTREACHED();
   return false;
 }