Add the basic code skeleton for system info event router

chrome/browser/extensions/api/system_info_storage/storage_info_provider_mac.cc

Index: chrome/browser/extensions/api/system_info_storage/storage_info_provider_mac.cc
diff --git a/chrome/browser/extensions/api/system_info_storage/storage_info_provider_mac.cc b/chrome/browser/extensions/api/system_info_storage/storage_info_provider_mac.cc
index 2c7f555b15a7f29997d97bb1964af1600173511d..dc7c04fff421bc6a832efd2951dde69b6798bb09 100644
--- a/chrome/browser/extensions/api/system_info_storage/storage_info_provider_mac.cc
+++ b/chrome/browser/extensions/api/system_info_storage/storage_info_provider_mac.cc
@@ -19,19 +19,31 @@ class StorageInfoProviderMac : public StorageInfoProvider {
   virtual ~StorageInfoProviderMac() {}
 
   virtual bool QueryInfo(StorageInfo* info) OVERRIDE;
-  virtual bool QueryUnitInfo(const std::string& id,
+  virtual bool QueryUnitInfo(const FilePath::StringType& path,
                              StorageUnitInfo* info) OVERRIDE;
+
+ private:
+  virtual bool PlatformStartWatching(Delegate* delegate) OVERRIDE;
+  virtual bool PlatformStopWatching() OVERRIDE;
 };
 
 bool StorageInfoProviderMac::QueryInfo(StorageInfo* info) {
   return false;
 }
 
-bool StorageInfoProviderMac::QueryUnitInfo(const std::string& id,
+bool StorageInfoProviderMac::QueryUnitInfo(const FilePath::StringType& path,
                                            StorageUnitInfo* info) {
   return false;
 }
 
+bool StorageInfoProviderMac::PlatformStartWatching(Delegate* delegate) {
+  return false;
+}
+
+bool StorageInfoProviderMac::PlatformStopWatching() {
+  return false;
+}
+
 }  // namespace
 
 // static