Deprecate PathService::Get(..., wstring*) and use FilePath instead.

base/path_service.cc

Index: base/path_service.cc
diff --git a/base/path_service.cc b/base/path_service.cc
index da172b3656d291a108908cd1ae74156949f17855..4a4c100a7b006c63f058c36e894064104a8ca14b 100644
--- a/base/path_service.cc
+++ b/base/path_service.cc
@@ -188,6 +188,7 @@ bool PathService::Get(int key, FilePath* result) {
   return true;
 }
 
+#if defined(OS_WIN)
 // static
 bool PathService::Get(int key, std::wstring* result) {
   // Deprecated compatibility function.
@@ -197,6 +198,7 @@ bool PathService::Get(int key, std::wstring* result) {
   *result = path.ToWStringHack();
   return true;
 }
+#endif
 
 bool PathService::IsOverridden(int key) {
   PathData* path_data = GetPathData();