SyncFS: Introduce SyncFileSystemBackend

webkit/browser/fileapi/sandbox_file_system_backend.cc

Index: webkit/browser/fileapi/sandbox_file_system_backend.cc
diff --git a/webkit/browser/fileapi/sandbox_file_system_backend.cc b/webkit/browser/fileapi/sandbox_file_system_backend.cc
index 1c034c9021c5725b7ae89a5201f3897673ce36f2..6fbc43ffaf8ea6660d126eb44833cda248723355 100644
--- a/webkit/browser/fileapi/sandbox_file_system_backend.cc
+++ b/webkit/browser/fileapi/sandbox_file_system_backend.cc
@@ -64,7 +64,6 @@ enum FileSystemError {
 
 const char kTemporaryOriginsCountLabel[] = "FileSystem.TemporaryOriginsCount";
 const char kPersistentOriginsCountLabel[] = "FileSystem.PersistentOriginsCount";
-const char kSyncableOriginsCountLabel[] = "FileSystem.SyncableOriginsCount";
 
 // Restricted names.
 // http://dev.w3.org/2009/dap/file-system/file-dir-sys.html#naming-restrictions
@@ -98,11 +97,11 @@ class ObfuscatedOriginEnumerator
 };
 
 void DidOpenFileSystem(
-    base::WeakPtr<SandboxFileSystemBackend> mount_point_provider,
+    base::WeakPtr<SandboxFileSystemBackend> file_system_backend,
     const base::Callback<void(base::PlatformFileError error)>& callback,
     base::PlatformFileError* error) {
-  if (mount_point_provider.get())
-    mount_point_provider.get()->CollectOpenFileSystemMetrics(*error);
+  if (file_system_backend.get())
+    file_system_backend.get()->CollectOpenFileSystemMetrics(*error);
   callback.Run(*error);
 }
 
@@ -134,29 +133,32 @@ void OpenFileSystemOnFileThread(
 
 SandboxFileSystemBackend::SandboxFileSystemBackend(
     SandboxContext* sandbox_context,
+    base::SequencedTaskRunner* file_task_runner,
     const FileSystemOptions& file_system_options)
-    : file_system_options_(file_system_options),
+    : file_task_runner_(file_task_runner),
+      file_system_options_(file_system_options),
       sandbox_context_(sandbox_context),
       enable_temporary_file_system_in_incognito_(false),
       enable_usage_tracking_(
           !CommandLine::ForCurrentProcess()->HasSwitch(
               kDisableUsageTracking)),
       weak_factory_(this) {
+  // SyncFileSystemBackend is instantiated with null context.
+  if (!sandbox_context)
+    return;
+
   // Set quota observers.
   if (enable_usage_tracking_) {
     update_observers_ = update_observers_.AddObserver(
-        sandbox_context_->quota_observer(),
-        sandbox_context_->file_task_runner());
+        sandbox_context_->quota_observer(), file_task_runner_.get());
     access_observers_ = access_observers_.AddObserver(
         sandbox_context_->quota_observer(), NULL);
   }
 
-  syncable_update_observers_ = update_observers_;
-
-  if (!sandbox_context_->file_task_runner()->RunsTasksOnCurrentThread()) {
+  if (!file_task_runner->RunsTasksOnCurrentThread()) {
     // Post prepopulate task only if it's not already running on
     // file_task_runner (which implies running in tests).
-    sandbox_context_->file_task_runner()->PostTask(
+    file_task_runner->PostTask(
         FROM_HERE,
         base::Bind(&ObfuscatedFileUtil::MaybePrepopulateDatabase,
                   base::Unretained(sandbox_sync_file_util())));
@@ -168,9 +170,7 @@ SandboxFileSystemBackend::~SandboxFileSystemBackend() {
 
 bool SandboxFileSystemBackend::CanHandleType(FileSystemType type) const {
   return type == kFileSystemTypeTemporary ||
-         type == kFileSystemTypePersistent ||
-         type == kFileSystemTypeSyncable ||
-         type == kFileSystemTypeSyncableForInternalSync;
+         type == kFileSystemTypePersistent;
 }
 
 void SandboxFileSystemBackend::InitializeFileSystem(
@@ -206,7 +206,7 @@ void SandboxFileSystemBackend::InitializeFileSystem(
   std::string name = GetFileSystemName(origin_url, type);
 
   base::PlatformFileError* error_ptr = new base::PlatformFileError;
-  sandbox_context_->file_task_runner()->PostTaskAndReply(
+  file_task_runner_->PostTaskAndReply(
       FROM_HERE,
       base::Bind(&OpenFileSystemOnFileThread,
                  sandbox_sync_file_util(),
@@ -222,20 +222,22 @@ void SandboxFileSystemBackend::InitializeFileSystem(
 
   // Schedule full usage recalculation on the next launch without
   // --disable-file-system-usage-tracking.
-  sandbox_context_->file_task_runner()->PostTask(
+  file_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&SandboxFileSystemBackend::InvalidateUsageCacheOnFileThread,
                  sandbox_sync_file_util(), origin_url, type, usage_cache()));
 };
 
 FileSystemFileUtil* SandboxFileSystemBackend::GetFileUtil(
-    FileSystemType type) {
+    FileSystemType type,
+    const FileSystemContext* context) {
   DCHECK(sandbox_context_);
   return sandbox_context_->sync_file_util();
 }
 
 AsyncFileUtil* SandboxFileSystemBackend::GetAsyncFileUtil(
-    FileSystemType type) {
+    FileSystemType type,
+    const FileSystemContext* context) {
   DCHECK(sandbox_context_);
   return sandbox_context_->file_util();
 }
@@ -260,16 +262,6 @@ FileSystemOperation* SandboxFileSystemBackend::CreateFileSystemOperation(
 
   scoped_ptr<FileSystemOperationContext> operation_context(
       new FileSystemOperationContext(context));
-
-  // Copy the observer lists (assuming we only have small number of observers).
-  if (url.type() == kFileSystemTypeSyncable) {
-    operation_context->set_update_observers(syncable_update_observers_);
-    operation_context->set_change_observers(syncable_change_observers_);
-    return new sync_file_system::SyncableFileSystemOperation(
-        url, context, operation_context.Pass());
-  }
-
-  // For regular sandboxed types.
   operation_context->set_update_observers(update_observers_);
   operation_context->set_change_observers(change_observers_);
 
@@ -367,9 +359,6 @@ void SandboxFileSystemBackend::GetOriginsForTypeOnFileThread(
     case kFileSystemTypePersistent:
       UMA_HISTOGRAM_COUNTS(kPersistentOriginsCountLabel, origins->size());
       break;
-    case kFileSystemTypeSyncable:
-      UMA_HISTOGRAM_COUNTS(kSyncableOriginsCountLabel, origins->size());
-      break;
     default:
       break;
   }
@@ -458,8 +447,6 @@ void SandboxFileSystemBackend::AddFileUpdateObserver(
     base::SequencedTaskRunner* task_runner) {
   DCHECK(CanHandleType(type));
   UpdateObserverList* list = &update_observers_;
-  if (type == kFileSystemTypeSyncable)
-    list = &syncable_update_observers_;
   *list = list->AddObserver(observer, task_runner);
 }
 
@@ -469,8 +456,6 @@ void SandboxFileSystemBackend::AddFileChangeObserver(
     base::SequencedTaskRunner* task_runner) {
   DCHECK(CanHandleType(type));
   ChangeObserverList* list = &change_observers_;
-  if (type == kFileSystemTypeSyncable)
-    list = &syncable_change_observers_;
   *list = list->AddObserver(observer, task_runner);
 }
 
@@ -485,16 +470,12 @@ void SandboxFileSystemBackend::AddFileAccessObserver(
 const UpdateObserverList* SandboxFileSystemBackend::GetUpdateObservers(
     FileSystemType type) const {
   DCHECK(CanHandleType(type));
-  if (type == kFileSystemTypeSyncable)
-    return &syncable_update_observers_;
   return &update_observers_;
 }
 
 const ChangeObserverList* SandboxFileSystemBackend::GetChangeObservers(
     FileSystemType type) const {
   DCHECK(CanHandleType(type));
-  if (type == kFileSystemTypeSyncable)
-    return &syncable_change_observers_;
   return &change_observers_;
 }