Adding support to retrieve remaining and total space on disk/file shelf.

chrome/browser/chromeos/cros/mount_library.h

Index: chrome/browser/chromeos/cros/mount_library.h
diff --git a/chrome/browser/chromeos/cros/mount_library.h b/chrome/browser/chromeos/cros/mount_library.h
index 8108f442faa607b109fef504ebde6d8eae73d66d..c4c7bec90d60febcdeccc5739c0107f866e8a2de 100644
--- a/chrome/browser/chromeos/cros/mount_library.h
+++ b/chrome/browser/chromeos/cros/mount_library.h
@@ -55,6 +55,9 @@ class MountLibcrosProxy {
   virtual void CallGetDiskProperties(const char* device_path,
                                      GetDiskPropertiesCallback callback,
                                      void* object) = 0;
+  virtual void CallGetSizeStats(const char* mount_path,
+                                GetSizeStatsCallback callback,
+                                void* object) = 0;
   virtual MountEventConnection MonitorCrosDisks(MountEventMonitor monitor,
       MountCompletedMonitor mount_complete_monitor,
       void* object) = 0;
@@ -170,6 +173,15 @@ class MountLibrary {
                                 const MountPointInfo& mount_info) = 0;
   };
 
+  class CallbackDelegate {
+   public:
+    virtual ~CallbackDelegate() {}
+    virtual void GetSizeStatsCallback(const char* mount_path,
+                                      bool success,
+                                      size_t total_size_kb,
+                                      size_t remaining_size_kb) = 0;
+  };
+
   virtual ~MountLibrary() {}
   virtual void AddObserver(Observer* observer) = 0;
   virtual void RemoveObserver(Observer* observer) = 0;
@@ -183,6 +195,10 @@ class MountLibrary {
   // |path| is device's mount path.
   virtual void UnmountPath(const char* path) = 0;
 
+  // Retrieves total and remaining available size on |mount_path|.
+  virtual void GetSizeStats(const char* mount_path,
+                            CallbackDelegate* callback_delegate) = 0;
+
   // Formats device given its file path.
   // Example: file_path: /dev/sdb1
   virtual void FormatUnmountedDevice(const char* file_path) = 0;