drive: Introduce DriveSystemServiceObserver

Move DriveFileSystem::NotifyFileSystemMounted() and
NotifyFileSystemToBeUnmounted() to DriveSystemServiceObserver
in favor of less things to have in DriveFileSystem

BUG=231788
TEST=none

Review URL: https://codereview.chromium.org/13866050

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@194529 0039d316-1c4b-4281-b951-d872f2087c98

12 files changed, 54 insertions, 59 deletions

diff --git a/chrome/browser/chromeos/drive/drive_file_system.cc b/chrome/browser/chromeos/drive/drive_file_system.cc
index b1f7ab5..6a60225 100644
--- a/chrome/browser/chromeos/drive/drive_file_system.cc
+++ b/chrome/browser/chromeos/drive/drive_file_system.cc
@@ -1298,24 +1298,6 @@ void DriveFileSystem::OnInitialFeedLoaded() {
                     OnInitialLoadFinished());
 }
 
-void DriveFileSystem::NotifyFileSystemMounted() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  DVLOG(1) << "File System is mounted";
-  // Notify the observers that the file system is mounted.
-  FOR_EACH_OBSERVER(DriveFileSystemObserver, observers_,
-                    OnFileSystemMounted());
-}
-
-void DriveFileSystem::NotifyFileSystemToBeUnmounted() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  DVLOG(1) << "File System is to be unmounted";
-  // Notify the observers that the file system is being unmounted.
-  FOR_EACH_OBSERVER(DriveFileSystemObserver, observers_,
-                    OnFileSystemBeingUnmounted());
-}
-
 void DriveFileSystem::AddUploadedFile(
     scoped_ptr<google_apis::ResourceEntry> entry,
     const base::FilePath& file_content_path,
diff --git a/chrome/browser/chromeos/drive/drive_file_system.h b/chrome/browser/chromeos/drive/drive_file_system.h
index 4d8a316..4154336 100644
--- a/chrome/browser/chromeos/drive/drive_file_system.h
+++ b/chrome/browser/chromeos/drive/drive_file_system.h
@@ -66,8 +66,6 @@ class DriveFileSystem : public DriveFileSystemInterface,
   virtual void Initialize() OVERRIDE;
   virtual void AddObserver(DriveFileSystemObserver* observer) OVERRIDE;
   virtual void RemoveObserver(DriveFileSystemObserver* observer) OVERRIDE;
-  virtual void NotifyFileSystemMounted() OVERRIDE;
-  virtual void NotifyFileSystemToBeUnmounted() OVERRIDE;
   virtual void CheckForUpdates() OVERRIDE;
   virtual void GetEntryInfoByResourceId(
       const std::string& resource_id,
diff --git a/chrome/browser/chromeos/drive/drive_file_system_interface.h b/chrome/browser/chromeos/drive/drive_file_system_interface.h
index add7df3..7ae18dd 100644
--- a/chrome/browser/chromeos/drive/drive_file_system_interface.h
+++ b/chrome/browser/chromeos/drive/drive_file_system_interface.h
@@ -155,12 +155,6 @@ class DriveFileSystemInterface {
   virtual void AddObserver(DriveFileSystemObserver* observer) = 0;
   virtual void RemoveObserver(DriveFileSystemObserver* observer) = 0;
 
-  // Notifies the file system was just mounted.
-  virtual void NotifyFileSystemMounted() = 0;
-
-  // Notifies the file system is going to be unmounted.
-  virtual void NotifyFileSystemToBeUnmounted() = 0;
-
   // Checks for updates on the server.
   virtual void CheckForUpdates() = 0;
 
diff --git a/chrome/browser/chromeos/drive/drive_file_system_observer.h b/chrome/browser/chromeos/drive/drive_file_system_observer.h
index b075189..063ca34 100644
--- a/chrome/browser/chromeos/drive/drive_file_system_observer.h
+++ b/chrome/browser/chromeos/drive/drive_file_system_observer.h
@@ -32,14 +32,6 @@ class DriveFileSystemObserver {
   virtual void OnFeedFromServerLoaded() {
   }
 
-  // Triggered when the file system is mounted.
-  virtual void OnFileSystemMounted() {
-  }
-
-  // Triggered when the file system is being unmounted.
-  virtual void OnFileSystemBeingUnmounted() {
-  }
-
  protected:
   virtual ~DriveFileSystemObserver() {}
 };
diff --git a/chrome/browser/chromeos/drive/drive_system_service.cc b/chrome/browser/chromeos/drive/drive_system_service.cc
index d614465..a5095ff 100644
--- a/chrome/browser/chromeos/drive/drive_system_service.cc
+++ b/chrome/browser/chromeos/drive/drive_system_service.cc
@@ -191,6 +191,16 @@ void DriveSystemService::Shutdown() {
   RemoveDriveMountPoint();
 }
 
+void DriveSystemService::AddObserver(DriveSystemServiceObserver* observer) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  observers_.AddObserver(observer);
+}
+
+void DriveSystemService::RemoveObserver(DriveSystemServiceObserver* observer) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  observers_.RemoveObserver(observer);
+}
+
 bool DriveSystemService::IsDriveEnabled() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
@@ -309,14 +319,16 @@ void DriveSystemService::AddDriveMountPoint() {
 
   if (success) {
     event_logger_->Log("AddDriveMountPoint");
-    file_system_->NotifyFileSystemMounted();
+    FOR_EACH_OBSERVER(DriveSystemServiceObserver, observers_,
+                      OnFileSystemMounted());
   }
 }
 
 void DriveSystemService::RemoveDriveMountPoint() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 
-  file_system_->NotifyFileSystemToBeUnmounted();
+  FOR_EACH_OBSERVER(DriveSystemServiceObserver, observers_,
+                    OnFileSystemBeingUnmounted());
 
   fileapi::ExternalMountPoints* mount_points =
       BrowserContext::GetMountPoints(profile_);
diff --git a/chrome/browser/chromeos/drive/drive_system_service.h b/chrome/browser/chromeos/drive/drive_system_service.h
index 7e63a12..cb13044 100644
--- a/chrome/browser/chromeos/drive/drive_system_service.h
+++ b/chrome/browser/chromeos/drive/drive_system_service.h
@@ -11,6 +11,7 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/singleton.h"
 #include "base/memory/weak_ptr.h"
+#include "base/observer_list.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "chrome/browser/chromeos/drive/drive_file_error.h"
 #include "chrome/browser/chromeos/drive/drive_file_system_util.h"
@@ -40,6 +41,22 @@ class EventLogger;
 class FileWriteHelper;
 class StaleCacheFilesRemover;
 
+// Interface for classes that need to observe events from DriveSystemService.
+// All events are notified on UI thread.
+class DriveSystemServiceObserver {
+ public:
+  // Triggered when the file system is mounted.
+  virtual void OnFileSystemMounted() {
+  }
+
+  // Triggered when the file system is being unmounted.
+  virtual void OnFileSystemBeingUnmounted() {
+  }
+
+ protected:
+  virtual ~DriveSystemServiceObserver() {}
+};
+
 // DriveSystemService runs the Drive system, including the Drive file system
 // implementation for the file manager, and some other sub systems.
 //
@@ -65,6 +82,10 @@ class DriveSystemService : public ProfileKeyedService,
   // ProfileKeyedService override:
   virtual void Shutdown() OVERRIDE;
 
+  // Adds and removes the observer.
+  void AddObserver(DriveSystemServiceObserver* observer);
+  void RemoveObserver(DriveSystemServiceObserver* observer);
+
   google_apis::DriveServiceInterface* drive_service() {
     return drive_service_.get();
   }
@@ -152,6 +173,8 @@ class DriveSystemService : public ProfileKeyedService,
   scoped_ptr<StaleCacheFilesRemover> stale_cache_files_remover_;
   scoped_refptr<DriveFileSystemProxy> file_system_proxy_;
 
+  ObserverList<DriveSystemServiceObserver> observers_;
+
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<DriveSystemService> weak_ptr_factory_;
diff --git a/chrome/browser/chromeos/drive/fake_drive_file_system.cc b/chrome/browser/chromeos/drive/fake_drive_file_system.cc
index 211a21e..87f1852 100644
--- a/chrome/browser/chromeos/drive/fake_drive_file_system.cc
+++ b/chrome/browser/chromeos/drive/fake_drive_file_system.cc
@@ -42,14 +42,6 @@ void FakeDriveFileSystem::RemoveObserver(DriveFileSystemObserver* observer) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
 
-void FakeDriveFileSystem::NotifyFileSystemMounted() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-}
-
-void FakeDriveFileSystem::NotifyFileSystemToBeUnmounted() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-}
-
 void FakeDriveFileSystem::CheckForUpdates() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
 }
diff --git a/chrome/browser/chromeos/drive/fake_drive_file_system.h b/chrome/browser/chromeos/drive/fake_drive_file_system.h
index 254d953..1a83782 100644
--- a/chrome/browser/chromeos/drive/fake_drive_file_system.h
+++ b/chrome/browser/chromeos/drive/fake_drive_file_system.h
@@ -45,8 +45,6 @@ class FakeDriveFileSystem : public DriveFileSystemInterface {
   virtual void Initialize() OVERRIDE;
   virtual void AddObserver(DriveFileSystemObserver* observer) OVERRIDE;
   virtual void RemoveObserver(DriveFileSystemObserver* observer) OVERRIDE;
-  virtual void NotifyFileSystemMounted() OVERRIDE;
-  virtual void NotifyFileSystemToBeUnmounted() OVERRIDE;
   virtual void CheckForUpdates() OVERRIDE;
   virtual void GetEntryInfoByResourceId(
       const std::string& resource_id,
diff --git a/chrome/browser/chromeos/drive/mock_drive_file_system.h b/chrome/browser/chromeos/drive/mock_drive_file_system.h
index 8113399..9b0e81f 100644
--- a/chrome/browser/chromeos/drive/mock_drive_file_system.h
+++ b/chrome/browser/chromeos/drive/mock_drive_file_system.h
@@ -25,8 +25,6 @@ class MockDriveFileSystem : public DriveFileSystemInterface {
   MOCK_METHOD1(AddObserver, void(DriveFileSystemObserver* observer));
   MOCK_METHOD1(RemoveObserver,
                void(DriveFileSystemObserver* observer));
-  MOCK_METHOD0(NotifyFileSystemMounted, void());
-  MOCK_METHOD0(NotifyFileSystemToBeUnmounted, void());
   MOCK_METHOD0(CheckForUpdates, void());
   MOCK_METHOD2(GetEntryInfoByResourceId,
                void(const std::string& resource_id,
diff --git a/chrome/browser/chromeos/extensions/file_manager/drive_test_util.cc b/chrome/browser/chromeos/extensions/file_manager/drive_test_util.cc
index a7a1fc2..265961b 100644
--- a/chrome/browser/chromeos/extensions/file_manager/drive_test_util.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/drive_test_util.cc
@@ -20,31 +20,31 @@ const char kDriveMountPointName[] = "drive";
 
 // Helper class used to wait for |OnFileSystemMounted| event from a drive file
 // system.
-class DriveMountPointWaiter : public drive::DriveFileSystemObserver {
+class DriveMountPointWaiter : public drive::DriveSystemServiceObserver {
  public:
-  explicit DriveMountPointWaiter(drive::DriveFileSystemInterface* file_system)
-      : file_system_(file_system) {
-    file_system_->AddObserver(this);
+  explicit DriveMountPointWaiter(drive::DriveSystemService* system_service)
+      : system_service_(system_service) {
+    system_service_->AddObserver(this);
   }
 
   virtual ~DriveMountPointWaiter() {
-    file_system_->RemoveObserver(this);
+    system_service_->RemoveObserver(this);
   }
 
-  // DriveFileSystemObserver override.
+  // DriveSystemServiceObserver override.
   virtual void OnFileSystemMounted() OVERRIDE {
     // Note that it is OK for |run_loop_.Quit| to be called before
     // |run_loop_.Run|. In this case |Run| will return immediately.
     run_loop_.Quit();
   }
 
-  // Runs loop until the file_system_ gets mounted.
+  // Runs loop until the file system is mounted.
   void Wait() {
     run_loop_.Run();
   }
 
  private:
-  drive::DriveFileSystemInterface* file_system_;
+  drive::DriveSystemService* system_service_;
   base::RunLoop run_loop_;
 };
 
@@ -63,9 +63,9 @@ void WaitUntilDriveMountPointIsAdded(Profile* profile) {
   drive::DriveSystemService* system_service =
       drive::DriveSystemServiceFactory::FindForProfileRegardlessOfStates(
           profile);
-  DCHECK(system_service && system_service->file_system());
+  DCHECK(system_service);
 
-  DriveMountPointWaiter mount_point_waiter(system_service->file_system());
+  DriveMountPointWaiter mount_point_waiter(system_service);
 
   base::FilePath ignored;
   // GetRegisteredPath succeeds iff the mount point exists.
diff --git a/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.cc b/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.cc
index 8a1c14c..4cf9bd1 100644
--- a/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.cc
+++ b/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.cc
@@ -293,6 +293,7 @@ void FileManagerEventRouter::Shutdown() {
   DriveSystemService* system_service =
       DriveSystemServiceFactory::FindForProfileRegardlessOfStates(profile_);
   if (system_service) {
+    system_service->RemoveObserver(this);
     system_service->file_system()->RemoveObserver(this);
     system_service->drive_service()->RemoveObserver(this);
   }
@@ -322,6 +323,7 @@ void FileManagerEventRouter::ObserveFileSystemEvents() {
   DriveSystemService* system_service =
       DriveSystemServiceFactory::GetForProfileRegardlessOfStates(profile_);
   if (system_service) {
+    system_service->AddObserver(this);
     system_service->drive_service()->AddObserver(this);
     system_service->file_system()->AddObserver(this);
   }
diff --git a/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.h b/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.h
index 9a5b327..199f58e 100644
--- a/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.h
+++ b/chrome/browser/chromeos/extensions/file_manager/file_manager_event_router.h
@@ -16,6 +16,7 @@
 #include "base/synchronization/lock.h"
 #include "chrome/browser/chromeos/drive/drive_file_system_observer.h"
 #include "chrome/browser/chromeos/drive/drive_resource_metadata.h"
+#include "chrome/browser/chromeos/drive/drive_system_service.h"
 #include "chrome/browser/chromeos/net/connectivity_state_helper_observer.h"
 #include "chrome/browser/chromeos/system_key_event_listener.h"
 #include "chrome/browser/google_apis/drive_service_interface.h"
@@ -37,6 +38,7 @@ class FileManagerEventRouter
     : public chromeos::disks::DiskMountManager::Observer,
       public chromeos::ConnectivityStateHelperObserver,
       public chromeos::SystemKeyEventListener::ModifiersObserver,
+      public drive::DriveSystemServiceObserver,
       public drive::DriveFileSystemObserver,
       public google_apis::DriveServiceObserver {
  public:
@@ -109,9 +111,11 @@ class FileManagerEventRouter
       const google_apis::OperationProgressStatusList& list) OVERRIDE;
   virtual void OnRefreshTokenInvalid() OVERRIDE;
 
-  // drive::DriveFileSystemInterface::Observer overrides.
+  // drive::DriveFileSystemObserver overrides.
   virtual void OnDirectoryChanged(
       const base::FilePath& directory_path) OVERRIDE;
+
+  // drive::DriveSystemServiceObserver overrides.
   virtual void OnFileSystemMounted() OVERRIDE;
   virtual void OnFileSystemBeingUnmounted() OVERRIDE;