Add PathService::RemoveOverride to clear path overrides.

base/path_service.h

Index: base/path_service.h
diff --git a/base/path_service.h b/base/path_service.h
index e835a1f34e6b4ddd3c4f313145c30c5cc04ad0fb..40da55a2e21e1f36413b376930e19110249e831a 100644
--- a/base/path_service.h
+++ b/base/path_service.h
@@ -9,6 +9,7 @@
 
 #include "base/base_export.h"
 #include "base/base_paths.h"
+#include "base/gtest_prod_util.h"
 #include "build/build_config.h"
 
 class FilePath;
@@ -61,10 +62,14 @@ class BASE_EXPORT PathService {
   static void RegisterProvider(ProviderFunc provider,
                                int key_start,
                                int key_end);
+
  private:
-  static bool GetFromCache(int key, FilePath* path);
-  static bool GetFromOverrides(int key, FilePath* path);
-  static void AddToCache(int key, const FilePath& path);
+  FRIEND_TEST_ALL_PREFIXES(PathServiceTest, RemoveOverride);
+
+  // Removes an override for a special directory or file. Returns true if there
+  // was an override to remove or false if none was present.
+  // NOTE: This function is intended to be used by tests only!
+  static bool RemoveOverride(int key);
 };
 
 #endif  // BASE_PATH_SERVICE_H_