Extend the capability of SystemMonitor to support watching storage free space change

chrome/browser/system_monitor/removable_device_notifications_window_win.cc

Index: chrome/browser/system_monitor/removable_device_notifications_window_win.cc
diff --git a/chrome/browser/system_monitor/removable_device_notifications_window_win.cc b/chrome/browser/system_monitor/removable_device_notifications_window_win.cc
index 6cd090ee10bad44abc75bd13b7a9817118e7d6f1..7543371f77613b460177c0536545ab162ab539e0 100644
--- a/chrome/browser/system_monitor/removable_device_notifications_window_win.cc
+++ b/chrome/browser/system_monitor/removable_device_notifications_window_win.cc
@@ -79,10 +79,17 @@ void RemovableDeviceNotificationsWindowWin::Init() {
   window_ = CreateWindow(MAKEINTATOM(atom_), 0, 0, 0, 0, 0, 0, 0, 0, instance_,
                          0);
   SetWindowLongPtr(window_, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(this));
+
+  if (SystemMonitor::Get())
+    SystemMonitor::Get()->set_storage_free_space_delegate(this);
 }
 
 RemovableDeviceNotificationsWindowWin::~RemovableDeviceNotificationsWindowWin(
     ) {
+  if (SystemMonitor::Get() &&
+      SystemMonitor::Get()->storage_free_space_delegate())
+    SystemMonitor::Get()->set_storage_free_space_delegate(NULL);
+
   if (window_)
     DestroyWindow(window_);
 
@@ -161,6 +168,16 @@ RemovableDeviceNotificationsWindowWin::ProcessRemovableDeviceAttachedOnUIThread(
                                                         path.value());
 }
 
+void RemovableDeviceNotificationsWindowWin::StartWatchingStorage(
+    const FilePath& path) {
+  NOTIMPLEMENTED();
+}
+
+void RemovableDeviceNotificationsWindowWin::StopWatchingStorage(
+    const FilePath& path) {
+  NOTIMPLEMENTED();
+}
+
 LRESULT CALLBACK RemovableDeviceNotificationsWindowWin::WndProc(
     HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam) {
   switch (message) {