Some clean up in drive::file_system.

- Consolidate the naming and the argument order of each Operation's constructor.
See DriveOperations::Init. I chose the order:
(observer,scheduler,metadata,cache,file_system,task_runner).
- Remove comments mentioning to running thread. Now our code base
  is clean enough about thread safety, even without comments.
- Remove "callback must not be null" from private method comments.
- Fix incorrect #include and forward declarations.
- (Piggyback: One tiny irrelevant comment fix in file_system_util.h)

BUG=none

Review URL: https://chromiumcodereview.appspot.com/15047015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@200793 0039d316-1c4b-4281-b951-d872f2087c98

19 files changed, 224 insertions, 338 deletions

diff --git a/chrome/browser/chromeos/drive/file_system.cc b/chrome/browser/chromeos/drive/file_system.cc
index f42a428..b6a78f7 100644
--- a/chrome/browser/chromeos/drive/file_system.cc
+++ b/chrome/browser/chromeos/drive/file_system.cc
@@ -234,12 +234,12 @@ void FileSystem::Initialize() {
   SetupChangeListLoader();
 
   // Allocate the drive operation handlers.
-  drive_operations_.Init(scheduler_,
-                         this,  // FileSystemInterface
-                         cache_,
+  drive_operations_.Init(this,  // OperationObserver
+                         scheduler_,
                          resource_metadata_,
-                         blocking_task_runner_,
-                         this);  // OperationObserver
+                         cache_,
+                         this,  // FileSystemInterface
+                         blocking_task_runner_);
 
   PrefService* pref_service = profile_->GetPrefs();
   hide_hosted_docs_ = pref_service->GetBoolean(prefs::kDisableDriveHostedFiles);
diff --git a/chrome/browser/chromeos/drive/file_system/copy_operation.cc b/chrome/browser/chromeos/drive/file_system/copy_operation.cc
index be6029d..ae75595 100644
--- a/chrome/browser/chromeos/drive/file_system/copy_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/copy_operation.cc
@@ -56,27 +56,24 @@ std::string GetDocumentResourceIdOnBlockingPool(
 
 }  // namespace
 
-CopyOperation::CopyOperation(
-    JobScheduler* job_scheduler,
-    FileSystemInterface* file_system,
-    internal::ResourceMetadata* metadata,
-    internal::FileCache* cache,
-    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-    OperationObserver* observer)
-  : job_scheduler_(job_scheduler),
-    file_system_(file_system),
+CopyOperation::CopyOperation(base::SequencedTaskRunner* blocking_task_runner,
+                             OperationObserver* observer,
+                             JobScheduler* scheduler,
+                             internal::ResourceMetadata* metadata,
+                             internal::FileCache* cache,
+                             FileSystemInterface* file_system)
+  : blocking_task_runner_(blocking_task_runner),
+    observer_(observer),
+    scheduler_(scheduler),
     metadata_(metadata),
     cache_(cache),
-    blocking_task_runner_(blocking_task_runner),
-    observer_(observer),
-    create_file_operation_(new CreateFileOperation(job_scheduler,
-                                                   cache,
+    file_system_(file_system),
+    create_file_operation_(new CreateFileOperation(blocking_task_runner,
+                                                   observer,
+                                                   scheduler,
                                                    metadata,
-                                                   blocking_task_runner,
-                                                   observer)),
-    move_operation_(new MoveOperation(job_scheduler,
-                                      metadata,
-                                      observer)),
+                                                   cache)),
+    move_operation_(new MoveOperation(observer, scheduler, metadata)),
     weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
@@ -222,7 +219,7 @@ void CopyOperation::CopyHostedDocumentToDirectory(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
-  job_scheduler_->CopyHostedDocument(
+  scheduler_->CopyHostedDocument(
       resource_id,
       base::FilePath(new_name).AsUTF8Unsafe(),
       base::Bind(&CopyOperation::OnCopyHostedDocumentCompleted,
diff --git a/chrome/browser/chromeos/drive/file_system/copy_operation.h b/chrome/browser/chromeos/drive/file_system/copy_operation.h
index f1fadfd..4aa5596 100644
--- a/chrome/browser/chromeos/drive/file_system/copy_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/copy_operation.h
@@ -6,8 +6,10 @@
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_COPY_OPERATION_H_
 
 #include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/sequenced_task_runner.h"
 #include "chrome/browser/chromeos/drive/file_system_interface.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
@@ -26,6 +28,7 @@ class ResourceEntry;
 
 namespace internal {
 class FileCache;
+class ResourceMetadata;
 }  // namespace internal
 
 namespace file_system {
@@ -39,40 +42,37 @@ class OperationObserver;
 // metadata to reflect the new state.
 class CopyOperation {
  public:
-  CopyOperation(JobScheduler* job_scheduler,
-                FileSystemInterface* file_system,
+  CopyOperation(base::SequencedTaskRunner* blocking_task_runner,
+                OperationObserver* observer,
+                JobScheduler* scheduler,
                 internal::ResourceMetadata* metadata,
                 internal::FileCache* cache,
-                scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-                OperationObserver* observer);
-  virtual ~CopyOperation();
+                FileSystemInterface* file_system);
+  ~CopyOperation();
 
   // Performs the copy operation on the file at drive path |src_file_path|
   // with a target of |dest_file_path|. Invokes |callback| when finished with
   // the result of the operation. |callback| must not be null.
-  virtual void Copy(const base::FilePath& src_file_path,
-                    const base::FilePath& dest_file_path,
-                    const FileOperationCallback& callback);
+  void Copy(const base::FilePath& src_file_path,
+            const base::FilePath& dest_file_path,
+            const FileOperationCallback& callback);
 
   // Initiates transfer of |remote_src_file_path| to |local_dest_file_path|.
   // |remote_src_file_path| is the virtual source path on the Drive file system.
   // |local_dest_file_path| is the destination path on the local file system.
   //
-  // Must be called from *UI* thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  virtual void TransferFileFromRemoteToLocal(
-      const base::FilePath& remote_src_file_path,
-      const base::FilePath& local_dest_file_path,
-      const FileOperationCallback& callback);
+  void TransferFileFromRemoteToLocal(const base::FilePath& remote_src_file_path,
+                                     const base::FilePath& local_dest_file_path,
+                                     const FileOperationCallback& callback);
 
   // Initiates transfer of |local_src_file_path| to |remote_dest_file_path|.
   // |local_src_file_path| must be a file from the local file system.
   // |remote_dest_file_path| is the virtual destination path within Drive file
   // system.
   //
-  // Must be called from *UI* thread. |callback| is run on the calling thread.
   // |callback| must not be null.
-  virtual void TransferFileFromLocalToRemote(
+  void TransferFileFromLocalToRemote(
       const base::FilePath& local_src_file_path,
       const base::FilePath& remote_dest_file_path,
       const FileOperationCallback& callback);
@@ -98,9 +98,6 @@ class CopyOperation {
   // TransferFileFromRemoteToLocal. If GetFileByPath reports no error, calls
   // CopyLocalFileOnBlockingPool to copy |local_file_path| to
   // |local_dest_file_path|.
-  //
-  // Can be called from UI thread. |callback| is run on the calling thread.
-  // |callback| must not be null.
   void OnGetFileCompleteForTransferFile(
       const base::FilePath& local_dest_file_path,
       const FileOperationCallback& callback,
@@ -110,16 +107,12 @@ class CopyOperation {
 
   // Copies a hosted document with |resource_id| to the directory at |dir_path|
   // and names the copied document as |new_name|.
-  //
-  // Can be called from UI thread. |callback| is run on the calling thread.
-  // |callback| must not be null.
   void CopyHostedDocumentToDirectory(const base::FilePath& dir_path,
                                      const std::string& resource_id,
                                      const base::FilePath::StringType& new_name,
                                      const FileOperationCallback& callback);
 
   // Callback for handling document copy attempt.
-  // |callback| must not be null.
   void OnCopyHostedDocumentCompleted(
       const base::FilePath& dir_path,
       const FileOperationCallback& callback,
@@ -129,16 +122,12 @@ class CopyOperation {
   // Moves a file or directory at |file_path| in the root directory to
   // another directory at |dir_path|. This function does nothing if
   // |dir_path| points to the root directory.
-  //
-  // Can be called from UI thread. |callback| is run on the calling thread.
-  // |callback| must not be null.
   void MoveEntryFromRootDirectory(const base::FilePath& directory_path,
                                   const FileOperationCallback& callback,
                                   FileError error,
                                   const base::FilePath& file_path);
 
-  // Part of Copy(). Called after GetResourceEntryPairByPaths() is
-  // complete. |callback| must not be null.
+  // Part of Copy(). Called after GetResourceEntryPairByPaths() is complete.
   void CopyAfterGetResourceEntryPair(const base::FilePath& dest_file_path,
                                  const FileOperationCallback& callback,
                                  scoped_ptr<EntryInfoPairResult> result);
@@ -146,8 +135,6 @@ class CopyOperation {
   // Invoked upon completion of GetFileByPath initiated by Copy. If
   // GetFileByPath reports no error, calls TransferRegularFile to transfer
   // |local_file_path| to |remote_dest_file_path|.
-  //
-  // Can be called from UI thread. |callback| is run on the calling thread.
   void OnGetFileCompleteForCopy(const base::FilePath& remote_dest_file_path,
                                 const FileOperationCallback& callback,
                                 FileError error,
@@ -169,31 +156,26 @@ class CopyOperation {
   // Drive file system. If |resource_id| is a non-empty string, the transfer is
   // handled by CopyDocumentToDirectory. Otherwise, the transfer is handled by
   // TransferRegularFile.
-  //
-  // Must be called from *UI* thread. |callback| is run on the calling thread.
-  // |callback| must not be null.
   void TransferFileForResourceId(const base::FilePath& local_file_path,
                                  const base::FilePath& remote_dest_file_path,
                                  const FileOperationCallback& callback,
                                  const std::string& resource_id);
 
-  JobScheduler* job_scheduler_;
-  FileSystemInterface* file_system_;
-  internal::ResourceMetadata* metadata_;
-  internal::FileCache* cache_;
   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
   OperationObserver* observer_;
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
+  internal::FileCache* cache_;
+  FileSystemInterface* file_system_;
 
   // Uploading a new file is internally implemented by creating a dirty file.
   scoped_ptr<CreateFileOperation> create_file_operation_;
   // Copying a hosted document is internally implemented by using a move.
   scoped_ptr<MoveOperation> move_operation_;
 
-  // WeakPtrFactory bound to the UI thread.
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<CopyOperation> weak_ptr_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(CopyOperation);
 };
 
diff --git a/chrome/browser/chromeos/drive/file_system/create_directory_operation.cc b/chrome/browser/chromeos/drive/file_system/create_directory_operation.cc
index f84fb49..0e4b470 100644
--- a/chrome/browser/chromeos/drive/file_system/create_directory_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/create_directory_operation.cc
@@ -74,12 +74,12 @@ struct CreateDirectoryOperation::FindFirstMissingParentDirectoryParams {
 };
 
 CreateDirectoryOperation::CreateDirectoryOperation(
-    JobScheduler* job_scheduler,
-    internal::ResourceMetadata* metadata,
-    OperationObserver* observer)
-    : job_scheduler_(job_scheduler),
+    OperationObserver* observer,
+    JobScheduler* scheduler,
+    internal::ResourceMetadata* metadata)
+    : observer_(observer),
+      scheduler_(scheduler),
       metadata_(metadata),
-      observer_(observer),
       weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
@@ -142,7 +142,7 @@ void CreateDirectoryOperation::CreateDirectoryAfterFindFirstMissingPath(
     return;
   }
 
-  job_scheduler_->AddNewDirectory(
+  scheduler_->AddNewDirectory(
       result.last_dir_resource_id,
       result.first_missing_parent_path.BaseName().AsUTF8Unsafe(),
       base::Bind(&CreateDirectoryOperation::AddNewDirectory,
diff --git a/chrome/browser/chromeos/drive/file_system/create_directory_operation.h b/chrome/browser/chromeos/drive/file_system/create_directory_operation.h
index 42bfaa9..f12886a 100644
--- a/chrome/browser/chromeos/drive/file_system/create_directory_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/create_directory_operation.h
@@ -12,12 +12,9 @@
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/chromeos/drive/file_errors.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
-#include "googleurl/src/gurl.h"
 
 namespace google_apis {
-
 class ResourceEntry;
-
 }  // namespace google_apis
 
 namespace drive {
@@ -38,9 +35,9 @@ class OperationObserver;
 // local state and metadata to reflect the new state.
 class CreateDirectoryOperation {
  public:
-  CreateDirectoryOperation(JobScheduler* job_scheduler,
-                           internal::ResourceMetadata* metadata,
-                           OperationObserver* observer);
+  CreateDirectoryOperation(OperationObserver* observer,
+                           JobScheduler* scheduler,
+                           internal::ResourceMetadata* metadata);
   ~CreateDirectoryOperation();
 
   // Creates a new directory at |directory_path|.
@@ -144,15 +141,13 @@ class CreateDirectoryOperation {
       FileError error,
       scoped_ptr<ResourceEntry> entry);
 
-  JobScheduler* job_scheduler_;
-  internal::ResourceMetadata* metadata_;
   OperationObserver* observer_;
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
 
-  // WeakPtrFactory bound to the UI thread.
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<CreateDirectoryOperation> weak_ptr_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(CreateDirectoryOperation);
 };
 
diff --git a/chrome/browser/chromeos/drive/file_system/create_directory_operation_unittest.cc b/chrome/browser/chromeos/drive/file_system/create_directory_operation_unittest.cc
index 0226975..5a5bcc0 100644
--- a/chrome/browser/chromeos/drive/file_system/create_directory_operation_unittest.cc
+++ b/chrome/browser/chromeos/drive/file_system/create_directory_operation_unittest.cc
@@ -70,7 +70,7 @@ class CreateDirectoryOperationTest
     ASSERT_EQ(FILE_ERROR_OK, error);
 
     operation_.reset(
-        new CreateDirectoryOperation(scheduler_.get(), metadata_.get(), this));
+        new CreateDirectoryOperation(this, scheduler_.get(), metadata_.get()));
   }
 
   virtual void TearDown() OVERRIDE {
diff --git a/chrome/browser/chromeos/drive/file_system/create_file_operation.cc b/chrome/browser/chromeos/drive/file_system/create_file_operation.cc
index bdf53f4..532b0a9 100644
--- a/chrome/browser/chromeos/drive/file_system/create_file_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/create_file_operation.cc
@@ -34,16 +34,16 @@ void IgnoreError(const FileOperationCallback& callback, FileError error) {
 }  // namespace
 
 CreateFileOperation::CreateFileOperation(
-    JobScheduler* job_scheduler,
-    internal::FileCache* cache,
+    base::SequencedTaskRunner* blocking_task_runner,
+    OperationObserver* observer,
+    JobScheduler* scheduler,
     internal::ResourceMetadata* metadata,
-    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-    OperationObserver* observer)
-    : job_scheduler_(job_scheduler),
-      cache_(cache),
-      metadata_(metadata),
-      blocking_task_runner_(blocking_task_runner),
+    internal::FileCache* cache)
+    : blocking_task_runner_(blocking_task_runner),
       observer_(observer),
+      scheduler_(scheduler),
+      metadata_(metadata),
+      cache_(cache),
       weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
@@ -129,7 +129,7 @@ void CreateFileOperation::CreateFileAfterGetMimeType(
     bool got_content_type) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  job_scheduler_->CreateFile(
+  scheduler_->CreateFile(
       parent_resource_id,
       file_path,
       file_path.BaseName().value(),
diff --git a/chrome/browser/chromeos/drive/file_system/create_file_operation.h b/chrome/browser/chromeos/drive/file_system/create_file_operation.h
index a95f147..660d265 100644
--- a/chrome/browser/chromeos/drive/file_system/create_file_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/create_file_operation.h
@@ -6,25 +6,29 @@
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_CREATE_FILE_OPERATION_H_
 
 #include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
-#include "chrome/browser/chromeos/drive/resource_metadata.h"
+#include "base/sequenced_task_runner.h"
+#include "chrome/browser/chromeos/drive/file_errors.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
 namespace base {
 class FilePath;
-}
+}  // namespace base
 
 namespace google_apis {
 class ResourceEntry;
-}
+}  // namespace google_apis
 
 namespace drive {
 
 namespace internal {
 class FileCache;
+class ResourceMetadata;
 }  // namespace internal
 
+struct EntryInfoPairResult;
 class JobScheduler;
 class ResourceEntry;
 
@@ -37,12 +41,11 @@ class OperationObserver;
 // metadata to reflect the new state.
 class CreateFileOperation {
  public:
-  CreateFileOperation(
-      JobScheduler* job_scheduler,
-      internal::FileCache* cache,
-      internal::ResourceMetadata* metadata,
-      scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-      OperationObserver* observer);
+  CreateFileOperation(base::SequencedTaskRunner* blocking_task_runner,
+                      OperationObserver* observer,
+                      JobScheduler* scheduler,
+                      internal::ResourceMetadata* metadata,
+                      internal::FileCache* cache);
   ~CreateFileOperation();
 
   // Creates an empty file at |file_path| in the remote server. When the file
@@ -77,11 +80,11 @@ class CreateFileOperation {
                                     FileError error,
                                     const base::FilePath& drive_path);
 
-  JobScheduler* job_scheduler_;
-  internal::FileCache* cache_;
-  internal::ResourceMetadata* metadata_;
   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
   OperationObserver* observer_;
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
+  internal::FileCache* cache_;
 
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
diff --git a/chrome/browser/chromeos/drive/file_system/drive_operations.cc b/chrome/browser/chromeos/drive/file_system/drive_operations.cc
index 01ec103..ea3b576 100644
--- a/chrome/browser/chromeos/drive/file_system/drive_operations.cc
+++ b/chrome/browser/chromeos/drive/file_system/drive_operations.cc
@@ -27,57 +27,35 @@ DriveOperations::~DriveOperations() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
 
-void DriveOperations::Init(
-    JobScheduler* job_scheduler,
-    FileSystemInterface* file_system,
-    internal::FileCache* cache,
-    internal::ResourceMetadata* metadata,
-    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-    OperationObserver* observer) {
+void DriveOperations::Init(OperationObserver* observer,
+                           JobScheduler* scheduler,
+                           internal::ResourceMetadata* metadata,
+                           internal::FileCache* cache,
+                           FileSystemInterface* file_system,
+                           base::SequencedTaskRunner* blocking_task_runner) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  copy_operation_.reset(new file_system::CopyOperation(job_scheduler,
-                                                       file_system,
+  copy_operation_.reset(new file_system::CopyOperation(blocking_task_runner,
+                                                       observer,
+                                                       scheduler,
                                                        metadata,
                                                        cache,
-                                                       blocking_task_runner,
-                                                       observer));
+                                                       file_system));
   create_directory_operation_.reset(
-      new CreateDirectoryOperation(job_scheduler,
-                                   metadata,
-                                   observer));
-  create_file_operation_.reset(new CreateFileOperation(job_scheduler,
-                                                       cache,
+      new CreateDirectoryOperation(observer, scheduler, metadata));
+  create_file_operation_.reset(new CreateFileOperation(blocking_task_runner,
+                                                       observer,
+                                                       scheduler,
                                                        metadata,
-                                                       blocking_task_runner,
-                                                       observer));
-  move_operation_.reset(new MoveOperation(job_scheduler,
-                                          metadata,
-                                          observer));
-  remove_operation_.reset(new RemoveOperation(job_scheduler,
-                                              cache,
-                                              metadata,
-                                              observer));
-  update_operation_.reset(new UpdateOperation(cache,
-                                              metadata,
-                                              job_scheduler,
-                                              blocking_task_runner,
-                                              observer));
-  search_operation_.reset(new SearchOperation(blocking_task_runner,
-                                              job_scheduler,
-                                              metadata));
-}
-
-void DriveOperations::InitForTesting(CopyOperation* copy_operation,
-                                     MoveOperation* move_operation,
-                                     RemoveOperation* remove_operation,
-                                     UpdateOperation* update_operation) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  copy_operation_.reset(copy_operation);
-  move_operation_.reset(move_operation);
-  remove_operation_.reset(remove_operation);
-  update_operation_.reset(update_operation);
+                                                       cache));
+  move_operation_.reset(
+      new MoveOperation(observer, scheduler, metadata));
+  remove_operation_.reset(
+      new RemoveOperation(observer, scheduler, metadata, cache));
+  update_operation_.reset(
+      new UpdateOperation(observer, scheduler, metadata, cache));
+  search_operation_.reset(
+      new SearchOperation(blocking_task_runner, scheduler, metadata));
 }
 
 void DriveOperations::Copy(const base::FilePath& src_file_path,
@@ -113,11 +91,10 @@ void DriveOperations::TransferFileFromLocalToRemote(
                                                  callback);
 }
 
-void DriveOperations::CreateDirectory(
-    const base::FilePath& directory_path,
-    bool is_exclusive,
-    bool is_recursive,
-    const FileOperationCallback& callback) {
+void DriveOperations::CreateDirectory(const base::FilePath& directory_path,
+                                      bool is_exclusive,
+                                      bool is_recursive,
+                                      const FileOperationCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
diff --git a/chrome/browser/chromeos/drive/file_system/drive_operations.h b/chrome/browser/chromeos/drive/file_system/drive_operations.h
index 453377a..d8c5dca 100644
--- a/chrome/browser/chromeos/drive/file_system/drive_operations.h
+++ b/chrome/browser/chromeos/drive/file_system/drive_operations.h
@@ -6,21 +6,20 @@
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_DRIVE_OPERATIONS_H_
 
 #include "base/memory/scoped_ptr.h"
-#include "base/sequenced_task_runner.h"
 #include "chrome/browser/chromeos/drive/file_system_interface.h"
-#include "chrome/browser/chromeos/drive/resource_metadata.h"
 
 namespace base {
 class FilePath;
+class SequencedTaskRunner;
 }  // namespace base
 
 namespace drive {
 
-class FileSystemInterface;
 class JobScheduler;
 
 namespace internal {
 class FileCache;
+class ResourceMetadata;
 }  // namespace internal
 
 namespace file_system {
@@ -31,8 +30,8 @@ class CreateFileOperation;
 class MoveOperation;
 class OperationObserver;
 class RemoveOperation;
-class UpdateOperation;
 class SearchOperation;
+class UpdateOperation;
 
 // Callback for DriveOperations::Search.
 // On success, |error| is FILE_ERROR_OK, and remaining arguments are valid to
@@ -56,18 +55,12 @@ class DriveOperations {
   ~DriveOperations();
 
   // Allocates the operation objects and initializes the operation pointers.
-  void Init(JobScheduler* job_scheduler,
-            FileSystemInterface* file_system,
-            internal::FileCache* cache,
+  void Init(OperationObserver* observer,
+            JobScheduler* scheduler,
             internal::ResourceMetadata* metadata,
-            scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-            OperationObserver* observer);
-
-  // Initializes the operation pointers.  For testing only.
-  void InitForTesting(CopyOperation* copy_operation,
-                      MoveOperation* move_operation,
-                      RemoveOperation* remove_operation,
-                      UpdateOperation* update_operation);
+            internal::FileCache* cache,
+            FileSystemInterface* file_system,
+            base::SequencedTaskRunner* blocking_task_runner);
 
   // Wrapper function for create_directory_operation_.
   // |callback| must not be null.
diff --git a/chrome/browser/chromeos/drive/file_system/move_operation.cc b/chrome/browser/chromeos/drive/file_system/move_operation.cc
index 3053bef..c7e490a 100644
--- a/chrome/browser/chromeos/drive/file_system/move_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/move_operation.cc
@@ -5,7 +5,6 @@
 #include "chrome/browser/chromeos/drive/file_system/move_operation.h"
 
 #include "chrome/browser/chromeos/drive/drive.pb.h"
-#include "chrome/browser/chromeos/drive/file_cache.h"
 #include "chrome/browser/chromeos/drive/file_system/operation_observer.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/drive/job_scheduler.h"
@@ -16,12 +15,12 @@ using content::BrowserThread;
 namespace drive {
 namespace file_system {
 
-MoveOperation::MoveOperation(JobScheduler* job_scheduler,
-                             internal::ResourceMetadata* metadata,
-                             OperationObserver* observer)
-  : job_scheduler_(job_scheduler),
+MoveOperation::MoveOperation(OperationObserver* observer,
+                             JobScheduler* scheduler,
+                             internal::ResourceMetadata* metadata)
+  : observer_(observer),
+    scheduler_(scheduler),
     metadata_(metadata),
-    observer_(observer),
     weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
@@ -153,13 +152,13 @@ void MoveOperation::Rename(const std::string& src_id,
       new_name_has_hosted_extension ? new_name.RemoveExtension() : new_name);
 
   // Rename on the server.
-  job_scheduler_->RenameResource(src_id,
-                                 new_name_arg.AsUTF8Unsafe(),
-                                 base::Bind(&MoveOperation::RenameLocally,
-                                            weak_ptr_factory_.GetWeakPtr(),
-                                            src_path,
-                                            new_name_arg,
-                                            callback));
+  scheduler_->RenameResource(src_id,
+                             new_name_arg.AsUTF8Unsafe(),
+                             base::Bind(&MoveOperation::RenameLocally,
+                                        weak_ptr_factory_.GetWeakPtr(),
+                                        src_path,
+                                        new_name_arg,
+                                        callback));
 }
 
 void MoveOperation::RenameLocally(const base::FilePath& src_path,
@@ -184,7 +183,7 @@ void MoveOperation::AddToDirectory(const std::string& src_id,
                                    const FileMoveCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  job_scheduler_->AddResourceToDirectory(
+  scheduler_->AddResourceToDirectory(
       dest_dir_id, src_id,
       base::Bind(&MoveOperation::AddToDirectoryLocally,
                  weak_ptr_factory_.GetWeakPtr(),
@@ -213,7 +212,7 @@ void MoveOperation::RemoveFromDirectory(
     const FileOperationCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  job_scheduler_->RemoveResourceFromDirectory(
+  scheduler_->RemoveResourceFromDirectory(
       directory_resource_id,
       resource_id,
       base::Bind(&MoveOperation::RemoveFromDirectoryCompleted,
diff --git a/chrome/browser/chromeos/drive/file_system/move_operation.h b/chrome/browser/chromeos/drive/file_system/move_operation.h
index 61fac1a..ec18427 100644
--- a/chrome/browser/chromeos/drive/file_system/move_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/move_operation.h
@@ -11,21 +11,15 @@
 #include "chrome/browser/chromeos/drive/resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class GURL;
-
 namespace base {
 class FilePath;
-}
+}  // namespace base;
 
 namespace drive {
 
 class JobScheduler;
 class ResourceEntry;
 
-namespace internal {
-class ResourceMetadata;
-}  // namespace internal
-
 namespace file_system {
 
 class OperationObserver;
@@ -35,17 +29,17 @@ class OperationObserver;
 // metadata to reflect the new state.
 class MoveOperation {
  public:
-  MoveOperation(JobScheduler* job_scheduler,
-                internal::ResourceMetadata* metadata,
-                OperationObserver* observer);
-  virtual ~MoveOperation();
+  MoveOperation(OperationObserver* observer,
+                JobScheduler* scheduler,
+                internal::ResourceMetadata* metadata);
+  ~MoveOperation();
 
   // Performs the move operation on the file at drive path |src_file_path|
   // with a target of |dest_file_path|.  Invokes |callback| when finished with
   // the result of the operation. |callback| must not be null.
-  virtual void Move(const base::FilePath& src_file_path,
-                    const base::FilePath& dest_file_path,
-                    const FileOperationCallback& callback);
+  void Move(const base::FilePath& src_file_path,
+            const base::FilePath& dest_file_path,
+            const FileOperationCallback& callback);
  private:
   // Step 1 of Move(), called after the resource entry of the source and the
   // destination directory is obtained. It renames the resource in the source
@@ -121,11 +115,10 @@ class MoveOperation {
   void RemoveFromDirectoryCompleted(const FileOperationCallback& callback,
                                     google_apis::GDataErrorCode status);
 
-  JobScheduler* job_scheduler_;
-  internal::ResourceMetadata* metadata_;
   OperationObserver* observer_;
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
 
-  // WeakPtrFactory bound to the UI thread.
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<MoveOperation> weak_ptr_factory_;
diff --git a/chrome/browser/chromeos/drive/file_system/remove_operation.cc b/chrome/browser/chromeos/drive/file_system/remove_operation.cc
index 819df87..27904df 100644
--- a/chrome/browser/chromeos/drive/file_system/remove_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/remove_operation.cc
@@ -16,21 +16,14 @@ using content::BrowserThread;
 namespace drive {
 namespace file_system {
 
-namespace {
-
-void EmptyFileOperationCallback(FileError error) {}
-
-}  // namespace
-
-RemoveOperation::RemoveOperation(
-    JobScheduler* job_scheduler,
-    internal::FileCache* cache,
-    internal::ResourceMetadata* metadata,
-    OperationObserver* observer)
-  : job_scheduler_(job_scheduler),
-    cache_(cache),
+RemoveOperation::RemoveOperation(OperationObserver* observer,
+                                 JobScheduler* scheduler,
+                                 internal::ResourceMetadata* metadata,
+                                 internal::FileCache* cache)
+  : observer_(observer),
+    scheduler_(scheduler),
     metadata_(metadata),
-    observer_(observer),
+    cache_(cache),
     weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
@@ -39,10 +32,9 @@ RemoveOperation::~RemoveOperation() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
 
-void RemoveOperation::Remove(
-    const base::FilePath& file_path,
-    bool is_recursive,
-    const FileOperationCallback& callback) {
+void RemoveOperation::Remove(const base::FilePath& file_path,
+                             bool is_recursive,
+                             const FileOperationCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
@@ -66,9 +58,9 @@ void RemoveOperation::RemoveAfterGetResourceEntry(
     callback.Run(error);
     return;
   }
-  DCHECK(entry.get());
+  DCHECK(entry);
 
-  job_scheduler_->DeleteResource(
+  scheduler_->DeleteResource(
       entry->resource_id(),
       base::Bind(&RemoveOperation::RemoveResourceLocally,
                  weak_ptr_factory_.GetWeakPtr(),
@@ -96,7 +88,7 @@ void RemoveOperation::RemoveResourceLocally(
                  callback));
 
   cache_->RemoveOnUIThread(resource_id,
-                           base::Bind(&EmptyFileOperationCallback));
+                           base::Bind(&util::EmptyFileOperationCallback));
 }
 
 void RemoveOperation::NotifyDirectoryChanged(
diff --git a/chrome/browser/chromeos/drive/file_system/remove_operation.h b/chrome/browser/chromeos/drive/file_system/remove_operation.h
index a13686a..d8c29ee 100644
--- a/chrome/browser/chromeos/drive/file_system/remove_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/remove_operation.h
@@ -11,15 +11,12 @@
 #include "chrome/browser/chromeos/drive/file_errors.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class GURL;
-
 namespace base {
 class FilePath;
 }  // namespace base
 
 namespace drive {
 
-class FileSystem;
 class JobScheduler;
 class ResourceEntry;
 
@@ -37,52 +34,45 @@ class OperationObserver;
 // metadata to reflect the new state.
 class RemoveOperation {
  public:
-  RemoveOperation(JobScheduler* job_scheduler,
-                  internal::FileCache* cache,
+  RemoveOperation(OperationObserver* observer,
+                  JobScheduler* scheduler,
                   internal::ResourceMetadata* metadata,
-                  OperationObserver* observer);
-  virtual ~RemoveOperation();
+                  internal::FileCache* cache);
+  ~RemoveOperation();
 
   // Perform the remove operation on the file at drive path |file_path|.
   // Invokes |callback| when finished with the result of the operation.
   // |callback| must not be null.
-  virtual void Remove(const base::FilePath& file_path,
-                      bool is_recursive,
-                      const FileOperationCallback& callback);
+  void Remove(const base::FilePath& file_path,
+              bool is_recursive,
+              const FileOperationCallback& callback);
 
  private:
   // Part of Remove(). Called after GetResourceEntryByPath() is complete.
-  // |callback| must not be null.
-  void RemoveAfterGetResourceEntry(
-      const FileOperationCallback& callback,
-      FileError error,
-      scoped_ptr<ResourceEntry> entry);
+  void RemoveAfterGetResourceEntry(const FileOperationCallback& callback,
+                                   FileError error,
+                                   scoped_ptr<ResourceEntry> entry);
 
   // Callback for DriveServiceInterface::DeleteResource. Removes the entry with
   // |resource_id| from the local snapshot of the filesystem and the cache.
-  // |callback| must not be null.
-  void RemoveResourceLocally(
-      const FileOperationCallback& callback,
-      const std::string& resource_id,
-      google_apis::GDataErrorCode status);
+  void RemoveResourceLocally(const FileOperationCallback& callback,
+                             const std::string& resource_id,
+                             google_apis::GDataErrorCode status);
 
   // Sends notification for directory changes. Notifies of directory changes,
-  // and runs |callback| with |error|. |callback| must not be null.
-  void NotifyDirectoryChanged(
-      const FileOperationCallback& callback,
-      FileError error,
-      const base::FilePath& directory_path);
+  // and runs |callback| with |error|.
+  void NotifyDirectoryChanged(const FileOperationCallback& callback,
+                              FileError error,
+                              const base::FilePath& directory_path);
 
-  JobScheduler* job_scheduler_;
-  internal::FileCache* cache_;
-  internal::ResourceMetadata* metadata_;
   OperationObserver* observer_;
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
+  internal::FileCache* cache_;
 
-  // WeakPtrFactory bound to the UI thread.
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<RemoveOperation> weak_ptr_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(RemoveOperation);
 };
 
diff --git a/chrome/browser/chromeos/drive/file_system/search_operation.cc b/chrome/browser/chromeos/drive/file_system/search_operation.cc
index ae41a1f..a7084a2 100644
--- a/chrome/browser/chromeos/drive/file_system/search_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/search_operation.cc
@@ -10,7 +10,6 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/callback.h"
-#include "base/sequenced_task_runner.h"
 #include "base/task_runner_util.h"
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/drive/job_scheduler.h"
@@ -71,10 +70,10 @@ FileError RefreshEntriesOnBlockingPool(
 SearchOperation::SearchOperation(
     base::SequencedTaskRunner* blocking_task_runner,
     JobScheduler* scheduler,
-    internal::ResourceMetadata* resource_metadata)
+    internal::ResourceMetadata* metadata)
     : blocking_task_runner_(blocking_task_runner),
       scheduler_(scheduler),
-      resource_metadata_(resource_metadata),
+      metadata_(metadata),
       weak_ptr_factory_(this) {
 }
 
@@ -139,7 +138,7 @@ void SearchOperation::SearchAfterGetResourceList(
       blocking_task_runner_,
       FROM_HERE,
       base::Bind(&RefreshEntriesOnBlockingPool,
-                 resource_metadata_,
+                 metadata_,
                  base::Passed(&resource_list),
                  is_update_needed,
                  result_ptr),
diff --git a/chrome/browser/chromeos/drive/file_system/search_operation.h b/chrome/browser/chromeos/drive/file_system/search_operation.h
index 36a7594..fe82543 100644
--- a/chrome/browser/chromeos/drive/file_system/search_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/search_operation.h
@@ -6,21 +6,16 @@
 #define CHROME_BROWSER_CHROMEOS_DRIVE_FILE_SYSTEM_SEARCH_OPERATION_H_
 
 #include "base/basictypes.h"
-#include "base/callback_forward.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/sequenced_task_runner.h"
 #include "chrome/browser/chromeos/drive/file_errors.h"
 #include "chrome/browser/chromeos/drive/file_system/drive_operations.h"
-#include "chrome/browser/chromeos/drive/file_system_interface.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
 class GURL;
 
-namespace base {
-class SequencedTaskRunner;
-}  // namespace base
-
 namespace google_apis {
 class ResourceEntry;
 }  // namespace google_apis
@@ -39,9 +34,9 @@ namespace file_system {
 // sending the request to the drive API.
 class SearchOperation {
  public:
-  SearchOperation(base::SequencedTaskRunner* blocking_task_runner_,
-                  JobScheduler* job_scheduler,
-                  internal::ResourceMetadata* resource_metadata);
+  SearchOperation(base::SequencedTaskRunner* blocking_task_runner,
+                  JobScheduler* scheduler,
+                  internal::ResourceMetadata* metadata);
   ~SearchOperation();
 
   // Performs server side content search operation for |search_query|.
@@ -72,8 +67,8 @@ class SearchOperation {
       FileError error);
 
   scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
-  JobScheduler* scheduler_;  // Not owned.
-  internal::ResourceMetadata* resource_metadata_;  // Not owned.
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
 
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
diff --git a/chrome/browser/chromeos/drive/file_system/update_operation.cc b/chrome/browser/chromeos/drive/file_system/update_operation.cc
index 787c59d..ebd02e1 100644
--- a/chrome/browser/chromeos/drive/file_system/update_operation.cc
+++ b/chrome/browser/chromeos/drive/file_system/update_operation.cc
@@ -10,6 +10,7 @@
 #include "chrome/browser/chromeos/drive/file_system_util.h"
 #include "chrome/browser/chromeos/drive/job_scheduler.h"
 #include "chrome/browser/chromeos/drive/resource_entry_conversion.h"
+#include "chrome/browser/chromeos/drive/resource_metadata.h"
 #include "content/public/browser/browser_thread.h"
 
 using content::BrowserThread;
@@ -17,17 +18,14 @@ using content::BrowserThread;
 namespace drive {
 namespace file_system {
 
-UpdateOperation::UpdateOperation(
-    internal::FileCache* cache,
-    internal::ResourceMetadata* metadata,
-    JobScheduler* scheduler,
-    scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-    OperationObserver* observer)
-    : cache_(cache),
-      metadata_(metadata),
+UpdateOperation::UpdateOperation(OperationObserver* observer,
+                                 JobScheduler* scheduler,
+                                 internal::ResourceMetadata* metadata,
+                                 internal::FileCache* cache)
+    : observer_(observer),
       scheduler_(scheduler),
-      blocking_task_runner_(blocking_task_runner),
-      observer_(observer),
+      metadata_(metadata),
+      cache_(cache),
       weak_ptr_factory_(this) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
@@ -43,17 +41,15 @@ void UpdateOperation::UpdateFileByResourceId(
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(!callback.is_null());
 
-  // TODO(satorux): GetResourceEntryById() is called twice for
-  // UpdateFileByResourceId(). crbug.com/143873
   metadata_->GetResourceEntryByIdOnUIThread(
       resource_id,
-      base::Bind(&UpdateOperation::UpdateFileByEntryInfo,
+      base::Bind(&UpdateOperation::UpdateFileAfterGetEntryInfo,
                  weak_ptr_factory_.GetWeakPtr(),
                  context,
                  callback));
 }
 
-void UpdateOperation::UpdateFileByEntryInfo(
+void UpdateOperation::UpdateFileAfterGetEntryInfo(
     DriveClientContext context,
     const FileOperationCallback& callback,
     FileError error,
@@ -67,9 +63,9 @@ void UpdateOperation::UpdateFileByEntryInfo(
     return;
   }
 
-  DCHECK(entry.get());
+  DCHECK(entry);
   if (entry->file_info().is_directory()) {
-    callback.Run(FILE_ERROR_NOT_FOUND);
+    callback.Run(FILE_ERROR_NOT_A_FILE);
     return;
   }
 
@@ -78,7 +74,7 @@ void UpdateOperation::UpdateFileByEntryInfo(
   cache_->GetFileOnUIThread(
       entry_ptr->resource_id(),
       entry_ptr->file_specific_info().file_md5(),
-      base::Bind(&UpdateOperation::OnGetFileCompleteForUpdateFile,
+      base::Bind(&UpdateOperation::UpdateFileAfterGetFile,
                  weak_ptr_factory_.GetWeakPtr(),
                  context,
                  callback,
@@ -86,7 +82,7 @@ void UpdateOperation::UpdateFileByEntryInfo(
                  base::Passed(&entry)));
 }
 
-void UpdateOperation::OnGetFileCompleteForUpdateFile(
+void UpdateOperation::UpdateFileAfterGetFile(
     DriveClientContext context,
     const FileOperationCallback& callback,
     const base::FilePath& drive_file_path,
@@ -108,12 +104,12 @@ void UpdateOperation::OnGetFileCompleteForUpdateFile(
       entry->file_specific_info().content_mime_type(),
       "",  // etag
       context,
-      base::Bind(&UpdateOperation::OnUpdatedFileUploaded,
+      base::Bind(&UpdateOperation::UpdateFileAfterUpload,
                  weak_ptr_factory_.GetWeakPtr(),
                  callback));
 }
 
-void UpdateOperation::OnUpdatedFileUploaded(
+void UpdateOperation::UpdateFileAfterUpload(
     const FileOperationCallback& callback,
     google_apis::GDataErrorCode error,
     scoped_ptr<google_apis::ResourceEntry> resource_entry) {
@@ -128,11 +124,11 @@ void UpdateOperation::OnUpdatedFileUploaded(
 
   metadata_->RefreshEntryOnUIThread(
       ConvertToResourceEntry(*resource_entry),
-      base::Bind(&UpdateOperation::OnUpdatedFileRefreshed,
+      base::Bind(&UpdateOperation::UpdateFileAfterRefresh,
                  weak_ptr_factory_.GetWeakPtr(), callback));
 }
 
-void UpdateOperation::OnUpdatedFileRefreshed(
+void UpdateOperation::UpdateFileAfterRefresh(
     const FileOperationCallback& callback,
     FileError error,
     const base::FilePath& drive_file_path,
@@ -145,7 +141,7 @@ void UpdateOperation::OnUpdatedFileRefreshed(
     return;
   }
 
-  DCHECK(entry.get());
+  DCHECK(entry);
   DCHECK(entry->has_resource_id());
   DCHECK(entry->has_file_specific_info());
   DCHECK(entry->file_specific_info().has_file_md5());
diff --git a/chrome/browser/chromeos/drive/file_system/update_operation.h b/chrome/browser/chromeos/drive/file_system/update_operation.h
index d144d92..9e2e940 100644
--- a/chrome/browser/chromeos/drive/file_system/update_operation.h
+++ b/chrome/browser/chromeos/drive/file_system/update_operation.h
@@ -9,11 +9,8 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/chromeos/drive/file_system_interface.h"
-#include "chrome/browser/chromeos/drive/resource_metadata.h"
 #include "chrome/browser/google_apis/gdata_errorcode.h"
 
-class GURL;
-
 namespace base {
 class FilePath;
 }  // namespace base
@@ -25,6 +22,7 @@ class ResourceEntry;
 
 namespace internal {
 class FileCache;
+class ResourceMetadata;
 }  // namespace internal
 
 namespace file_system {
@@ -36,76 +34,53 @@ class OperationObserver;
 // metadata to reflect the new state.
 class UpdateOperation {
  public:
-  UpdateOperation(internal::FileCache* cache,
-                  internal::ResourceMetadata* metadata,
+  UpdateOperation(OperationObserver* observer,
                   JobScheduler* scheduler,
-                  scoped_refptr<base::SequencedTaskRunner> blocking_task_runner,
-                  OperationObserver* observer);
-  virtual ~UpdateOperation();
+                  internal::ResourceMetadata* metadata,
+                  internal::FileCache* cache);
+  ~UpdateOperation();
 
   // Updates a file by the given |resource_id| on the Drive server by
   // uploading an updated version. Used for uploading dirty files. The file
   // should already be present in the cache.
   //
-  // TODO(satorux): As of now, the function only handles files with the dirty
-  // bit committed. We should eliminate the restriction. crbug.com/134558.
-  //
-  // Can only be called from UI thread.  |callback| must not be null.
-  virtual void UpdateFileByResourceId(
-      const std::string& resource_id,
-      DriveClientContext context,
-      const FileOperationCallback& callback);
+  // |callback| must not be null.
+  void UpdateFileByResourceId(const std::string& resource_id,
+                              DriveClientContext context,
+                              const FileOperationCallback& callback);
 
  private:
-  // Part of UpdateFileByResourceId(). Called when
-  // ResourceMetadata::GetResourceEntryById() is complete.
-  // |callback| must not be null.
-  void UpdateFileByEntryInfo(
-      DriveClientContext context,
-      const FileOperationCallback& callback,
-      FileError error,
-      const base::FilePath& drive_file_path,
-      scoped_ptr<ResourceEntry> entry);
+  void UpdateFileAfterGetEntryInfo(DriveClientContext context,
+                                   const FileOperationCallback& callback,
+                                   FileError error,
+                                   const base::FilePath& drive_file_path,
+                                   scoped_ptr<ResourceEntry> entry);
+
+  void UpdateFileAfterGetFile(DriveClientContext context,
+                              const FileOperationCallback& callback,
+                              const base::FilePath& drive_file_path,
+                              scoped_ptr<ResourceEntry> entry,
+                              FileError error,
+                              const base::FilePath& cache_file_path);
 
-  // Part of UpdateFileByResourceId().
-  // Called when FileCache::GetFileOnUIThread() is completed for
-  // UpdateFileByResourceId().
-  // |callback| must not be null.
-  void OnGetFileCompleteForUpdateFile(
-      DriveClientContext context,
-      const FileOperationCallback& callback,
-      const base::FilePath& drive_file_path,
-      scoped_ptr<ResourceEntry> entry,
-      FileError error,
-      const base::FilePath& cache_file_path);
-
-  // Part of UpdateFileByResourceId().
-  // Called when DriveUploader::UploadUpdatedFile() is completed for
-  // UpdateFileByResourceId().
-  // |callback| must not be null.
-  void OnUpdatedFileUploaded(
+  void UpdateFileAfterUpload(
       const FileOperationCallback& callback,
       google_apis::GDataErrorCode error,
       scoped_ptr<google_apis::ResourceEntry> resource_entry);
 
-  // Part of UpdateFileByResourceId().
-  // |callback| must not be null.
-  void OnUpdatedFileRefreshed(const FileOperationCallback& callback,
+  void UpdateFileAfterRefresh(const FileOperationCallback& callback,
                               FileError error,
                               const base::FilePath& drive_file_path,
                               scoped_ptr<ResourceEntry> entry);
 
-  internal::FileCache* cache_;
-  internal::ResourceMetadata* metadata_;
-  JobScheduler* scheduler_;
-  scoped_refptr<base::SequencedTaskRunner> blocking_task_runner_;
   OperationObserver* observer_;
+  JobScheduler* scheduler_;
+  internal::ResourceMetadata* metadata_;
+  internal::FileCache* cache_;
 
-  // WeakPtrFactory bound to the UI thread.
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate the weak pointers before any other members are destroyed.
   base::WeakPtrFactory<UpdateOperation> weak_ptr_factory_;
-
   DISALLOW_COPY_AND_ASSIGN(UpdateOperation);
 };
 
diff --git a/chrome/browser/chromeos/drive/file_system_util.h b/chrome/browser/chromeos/drive/file_system_util.h
index b45820b..9dc727e 100644
--- a/chrome/browser/chromeos/drive/file_system_util.h
+++ b/chrome/browser/chromeos/drive/file_system_util.h
@@ -167,7 +167,7 @@ void ParseCacheFilePath(const base::FilePath& path,
                         std::string* md5,
                         std::string* extra_extension);
 
-// Callback type for PrepareWritablebase::FilePathAndRun.
+// Callback type for PrepareWritableFileAndRun.
 typedef base::Callback<void (FileError, const base::FilePath& path)>
     OpenFileCallback;