[SystemInfo API] Rewrite storage info provider using storage monitor impl

chrome/browser/extensions/api/system_info_storage/storage_info_provider.h

Index: chrome/browser/extensions/api/system_info_storage/storage_info_provider.h
diff --git a/chrome/browser/extensions/api/system_info_storage/storage_info_provider.h b/chrome/browser/extensions/api/system_info_storage/storage_info_provider.h
index 5ed7b5a65ae242af641b25278e6550f7c2f2f76b..ba6b50fda48d9450b7551080c5dcd957c2d2a19c 100644
--- a/chrome/browser/extensions/api/system_info_storage/storage_info_provider.h
+++ b/chrome/browser/extensions/api/system_info_storage/storage_info_provider.h
@@ -10,7 +10,7 @@
 #include "base/observer_list_threadsafe.h"
 #include "base/timer.h"
 #include "chrome/browser/extensions/api/system_info/system_info_provider.h"
-#include "chrome/browser/extensions/api/system_info_storage/storage_info_observer.h"
+#include "chrome/browser/extensions/api/system_info_storage/storage_free_space_observer.h"
 #include "chrome/browser/storage_monitor/removable_storage_observer.h"
 #include "chrome/browser/storage_monitor/storage_info.h"
 #include "chrome/common/extensions/api/experimental_system_info_storage.h"
@@ -25,45 +25,57 @@ extern const char kStorageTypeUnknown[];
 extern const char kStorageTypeFixed[];
 extern const char kStorageTypeRemovable[];
 
+// Build StorageUnitInfo struct from chrome::StorageInfo instance. The |unit|
+// parameter is the output value.
+void BuildStorageUnitInfo(const chrome::StorageInfo& info,
+    api::experimental_system_info_storage::StorageUnitInfo* unit);
+
 }  // namespace systeminfo
 
 typedef std::vector<linked_ptr<
-    api::experimental_system_info_storage::StorageUnitInfo> > StorageInfo;
+    api::experimental_system_info_storage::StorageUnitInfo> > StorageUnitList;
 
-class StorageInfoProvider
-    : public SystemInfoProvider<StorageInfo>,
-      public chrome::RemovableStorageObserver {
+class StorageInfoProvider : public SystemInfoProvider<StorageUnitList> {
  public:
+  StorageInfoProvider();
+
   // Get the single shared instance of StorageInfoProvider.
   static StorageInfoProvider* Get();
 
+  // SystemInfoProvider implementations:
+  virtual void StartQueryInfoImpl() OVERRIDE;
+  virtual bool QueryInfo(StorageUnitList* info) OVERRIDE;
+
   // Add and remove observer, both can be called from any thread.
-  void AddObserver(StorageInfoObserver* obs);
-  void RemoveObserver(StorageInfoObserver* obs);
+  void AddObserver(StorageFreeSpaceObserver* obs);
+  void RemoveObserver(StorageFreeSpaceObserver* obs);
 
   // Start and stop watching the given storage |id|.
   virtual void StartWatching(const std::string& id);
   virtual void StopWatching(const std::string& id);
 
-  // Get the information for the storage unit specified by the |id| parameter,
-  // and output the result to the |info|.
-  virtual bool QueryUnitInfo(const std::string& id,
-      api::experimental_system_info_storage::StorageUnitInfo* info) = 0;
+  // Returns all available storages, including fixed and removable.
+  virtual std::vector<chrome::StorageInfo> GetAllStorages() const;
+
+  // Get the storage mount path from |id|. The parameter |path| contains
+  // the output value. Return false if no such storage |id| is found.
+  virtual bool GetStoragePathFromId(const std::string& id,
+                                    base::FilePath* path);
+
+  // Return the amount of storage free space for |mount_path|,
+  // or -1 on failure.
+  virtual int64 GetStorageFreeSpace(const base::FilePath& mount_path);
 
  protected:
-  StorageInfoProvider();
   virtual ~StorageInfoProvider();
 
   void SetWatchingIntervalForTesting(size_t ms) { watching_interval_ = ms; }
 
  private:
-  typedef std::map<std::string, double> StorageIDToSizeMap;
+  typedef std::map<base::FilePath, double> StorageLocationToSizeMap;
 
-  // chrome::RemovableStorageObserver implementation.
-  virtual void OnRemovableStorageAttached(
-      const chrome::StorageInfo& info) OVERRIDE;
-  virtual void OnRemovableStorageDetached(
-      const chrome::StorageInfo& info) OVERRIDE;
+  void QueryAvailableCapacityOnBlockingPool();
+  void QueryInfoImplOnUIThread();
 
   // Query the new attached removable storage info on the blocking pool.
   void QueryAttachedStorageInfoOnBlockingPool(const std::string& id);
@@ -72,17 +84,15 @@ class StorageInfoProvider
   // Should be called on the UI thread.
   void CheckWatchedStorages();
 
-  // Check if the free space changes for the watched storages by iterating over
-  // the |storage_id_to_size_map_|. It is called on blocking pool.
-  void CheckWatchedStoragesOnBlockingPool();
-
-  // Provides an explicit hook that tests can wait for to determine that the
-  // call to CheckWatchedStorages() has completed.
-  virtual void OnCheckWatchedStoragesFinishedForTesting() {}
+  // Check if the free space of |mount_path| is changed. If so, it will
+  // notify the observers about the change event.
+  void CheckWatchedStorageOnBlockingPool(const std::string& id,
+                                         const base::FilePath& mount_path);
 
-  // Add and remove the storage to be watched.
-  void AddWatchedStorageOnBlockingPool(const std::string& id);
-  void RemoveWatchedStorageOnBlockingPool(const std::string& id);
+  // Add the storage identified by |mount_path| into watching list.
+  void AddWatchedStorageOnBlockingPool(const base::FilePath& mount_path);
+  // Remove the storage identified by |mount_path| from watching list.
+  void RemoveWatchedStorageOnBlockingPool(const base::FilePath& mount_path);
 
   void StartWatchingTimerOnUIThread();
   // Force to stop the watching timer or there is no any one storage to be
@@ -91,14 +101,14 @@ class StorageInfoProvider
 
   // Mapping of the storage being watched and the recent free space value. It
   // is maintained on the blocking pool.
-  StorageIDToSizeMap storage_id_to_size_map_;
+  StorageLocationToSizeMap storage_location_to_size_map_;
 
   // The timer used for watching the storage free space changes periodically.
   base::RepeatingTimer<StorageInfoProvider> watching_timer_;
 
   // The thread-safe observer list that observe the changes happening on the
   // storages.
-  scoped_refptr<ObserverListThreadSafe<StorageInfoObserver> > observers_;
+  scoped_refptr<ObserverListThreadSafe<StorageFreeSpaceObserver> > observers_;
 
   // The time interval for watching the free space change, in milliseconds.
   // Only changed for testing purposes.