Mark removable Drive caches for cryptohome.

components/drive/chromeos/file_cache.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_DRIVE_CHROMEOS_FILE_CACHE_H_
 #define COMPONENTS_DRIVE_CHROMEOS_FILE_CACHE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 126 matching lines @@
 
   // Removes the specified cache entry and delete cache files if available.
   FileError Remove(const std::string& id);
 
   // Removes all the files in the cache directory.
   bool ClearAll();
 
   // Initializes the cache. Returns true on success.
   bool Initialize();
 
+  // Returns if Drive cache migration for crbug/533750 should be invoked.

[hashimoto, 2016/05/02 08:29:20]

nit: crbug/533750 ".com" missing.
The same goes for others

[oka, 2016/05/09 14:27:40]

Done.

+  // Public for testing.
+  bool ShouldStartDriveCacheMigration();
+
   // Destroys this cache. This function posts a task to the blocking task
   // runner to safely delete the object.
   // Must be called on the UI thread.
   void Destroy();
 
   // Moves files in the cache directory which are not managed by FileCache to
   // |dest_directory|.
   // |recovered_cache_info| should contain cache info recovered from the trashed
   // metadata DB. It is used to ignore non-dirty files.
   bool RecoverFilesFromCacheDirectory(
       const base::FilePath& dest_directory,
       const ResourceMetadataStorage::RecoveredCacheInfoMap&
           recovered_cache_info);
 
-  // Migrates cache files from |from| directory to |to_files| directory with
-  // creating links in |to_links| directory if necessary. Returns true for
-  // success.
-  static bool MigrateCacheFiles(const base::FilePath& from,
-                                const base::FilePath& to_files,
-                                const base::FilePath& to_links,
-                                ResourceMetadataStorage* metadata_storage);
-
  private:
   friend class FileCacheTest;
 
   ~FileCache();
 
   // Returns absolute path of the file if it were cached or to be cached.
   //
   // Can be called on any thread.
   base::FilePath GetCacheFilePath(const std::string& id) const;
 
   // Checks whether the current thread is on the right sequenced worker pool
   // with the right sequence ID. If not, DCHECK will fail.
   void AssertOnSequencedWorkerPool();
 
   // Destroys the cache on the blocking pool.
   void DestroyOnBlockingPool();
 
   // Returns available space, while keeping
   // drive::internal::kMinFreeSpaceInBytes bytes on the disk.
   int64_t GetAvailableSpace();
 
   // Renames cache files from old "prefix:id.md5" format to the new format.
   // TODO(hashimoto): Remove this method at some point.
   bool RenameCacheFilesToNewFormat();
 
+  // Add appropriate file attributes to the Drive cache directory and files in

[hashimoto, 2016/05/02 08:29:20]

nit: "Add" -> "Adds".
https://google.github.io/styleguide/cppguide.html#Function_Comments
The same goes for others.

[oka, 2016/05/09 14:27:40]

Done.

Merged MigrateCacheFiles and ResolveMetadataInconsistency.

+  // it for crbug/533750. Returns true on success.
+  // Inconsistency between cache and metadata should be resolved before this

[hashimoto, 2016/05/02 08:29:20]

nit: How about "cache" -> "cache files" to avoid confusion, as everything is
related to cache in this class?

[oka, 2016/05/09 14:27:40]

Done.

+  // method is called.
+  bool MigrateCacheFiles();
+
+  // Resolve metadata inconsistency in case cryptohome removed cache files.
+  bool ResolveMetadataInconsistency();
+
   // This method must be called after writing to a cache file.
   // Used to implement OpenForWrite().
   void CloseForWrite(const std::string& id);
 
   // Returns true if the cache entry can be evicted.
   bool IsEvictable(const std::string& id, const ResourceEntry& entry);
 
   const base::FilePath cache_file_directory_;
 
   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
@@ skipping 21 matching lines @@
   // invalidate its weak pointers before any other members are destroyed.
   // This object should be accessed only on |blocking_task_runner_|.
   base::WeakPtrFactory<FileCache> weak_ptr_factory_;
   DISALLOW_COPY_AND_ASSIGN(FileCache);
 };
 
 }  // namespace internal
 }  // namespace drive
 
 #endif  // COMPONENTS_DRIVE_CHROMEOS_FILE_CACHE_H_