Sync: Support multiple setup UIs.

components/sync_driver/sync_service.h

 // Copyright 2015 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_SYNC_DRIVER_SYNC_SERVICE_H_
 #define COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_H_
 
 #include <memory>
 #include <string>
 
-#include "base/callback_forward.h"
+#include "base/callback.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "components/sync_driver/data_type_encryption_handler.h"
 #include "components/sync_driver/sync_service_observer.h"
 #include "google_apis/gaia/google_service_auth_error.h"
 #include "sync/internal_api/public/base/model_type.h"
 #include "sync/internal_api/public/connection_status.h"
 
@@ skipping 17 matching lines @@
 
 }  // namespace syncer
 
 namespace sync_driver {
 
 class DataTypeController;
 class LocalDeviceInfoProvider;
 class OpenTabsUIDelegate;
 class SyncClient;
 
+class SyncSetupInProgressHandle {

[maxbogue, 2016/06/09 20:04:14]

Comment explaining the purpose of this class?

[tommycli, 2016/06/10 00:04:16]

Done.

+ public:
+  explicit SyncSetupInProgressHandle(base::Closure on_destroy);
+  ~SyncSetupInProgressHandle();
+
+ private:
+  base::Closure on_destroy_;
+};
+
 class SyncService : public DataTypeEncryptionHandler {
  public:
   // Used to specify the kind of passphrase with which sync data is encrypted.
   enum PassphraseType {
     IMPLICIT,  // The user did not provide a custom passphrase for encryption.
                // We implicitly use the GAIA password in such cases.
     EXPLICIT,  // The user selected the "use custom passphrase" radio button
                // during sync setup and provided a passphrase.
   };
 
   // Passed as an argument to RequestStop to control whether or not the sync
   // backend should clear its data directory when it shuts down. See
   // RequestStop for more information.
   enum SyncStopDataFate {
     KEEP_DATA,
     CLEAR_DATA,
   };
 
   // Status of sync server connection, sync token and token request.
   struct SyncTokenStatus {
     SyncTokenStatus();
-    ~SyncTokenStatus();
 
     // Sync server connection status reported by sync backend.
     base::Time connection_status_update_time;
     syncer::ConnectionStatus connection_status;
 
     // Times when OAuth2 access token is requested and received.
     base::Time token_request_time;
     base::Time token_receive_time;
 
     // Error returned by OAuth2TokenService for token request and time when
@@ skipping 88 matching lines @@
 
   // Returns true if initial sync setup is in progress (does not return true
   // if the user is customizing sync after already completing setup once).
   // SyncService uses this to determine if it's OK to start syncing, or if the
   // user is still setting up the initial sync configuration.
   virtual bool IsFirstSetupInProgress() const = 0;
 
   // Called by the UI to notify the SyncService that UI is visible so it will
   // not start syncing. This tells sync whether it's safe to start downloading
   // data types yet (we don't start syncing until after sync setup is complete).
-  // The UI calls this as soon as any part of the signin wizard is displayed
-  // (even just the login UI).
-  // If |setup_in_progress| is false, this also kicks the sync engine to ensure
-  // that data download starts. In this case, |ReconfigureDatatypeManager| will
-  // get triggered.
-  virtual void SetSetupInProgress(bool setup_in_progress) = 0;
+  // The UI calls this and holds onto the instance for as long as any part of
+  // the signin wizard is displayed (even just the login UI).
+  // When the last outstanding handle is deleted, this kicks off the sync engine
+  // to ensure that data download starts. In this case,
+  // |ReconfigureDatatypeManager| will get triggered.
+  std::unique_ptr<SyncSetupInProgressHandle> GetSetupInProgressHandle();

[maxbogue, 2016/06/09 20:04:14]

Why is the implementation of this on this class and not ProfileSyncService? That
would let you get rid of the SetSetupInProgress method entirely, and move the
counter to PSS as well.

The split between this class and PSS is pretty weird right now, but if we're
gonna move things here I'd rather it be a separate process.

[tommycli, 2016/06/10 00:04:16]

Done.

 
   // Used by tests.
   virtual bool IsSetupInProgress() const = 0;
 
   // Whether the data types active for the current mode have finished
   // configuration.
   virtual bool ConfigurationDone() const = 0;
 
   virtual const GoogleServiceAuthError& GetAuthError() const = 0;
   virtual bool HasUnrecoverableError() const = 0;
@@ skipping 123 matching lines @@
   // returns them to the specified callback on this thread.
   //
   // These requests can live a long time and return when you least expect it.
   // For safety, the callback should be bound to some sort of WeakPtr<> or
   // scoped_refptr<>.
   virtual void GetAllNodes(
       const base::Callback<void(std::unique_ptr<base::ListValue>)>&
           callback) = 0;
 
  protected:
-  SyncService() {}
+  friend class SyncSetupInProgressHandle;

[maxbogue, 2016/06/09 20:04:13]

This shouldn't be necessary should it? That class doesn't actually require
direct access to this one.

[tommycli, 2016/06/10 00:04:16]

Done.

+
+  SyncService() : outstanding_setup_in_progress_handles_(0) {}

[maxbogue, 2016/06/09 20:04:13]

You can just use = 0 on the declaration below now.

[tommycli, 2016/06/10 00:04:16]

Done.

+
+  // Called internally by the GetSetupInProgressHandle mechanism.
+  // This should not be called directly (except by the Android wrapper).

[maxbogue, 2016/06/09 20:04:14]

What Android wrapper?

[tommycli, 2016/06/10 00:04:15]

Done. Method removed.

+  virtual void SetSetupInProgress(bool setup_in_progress) = 0;
+
+  int outstanding_setup_in_progress_handles_;

[maxbogue, 2016/06/09 20:04:13]

Comment please.

[tommycli, 2016/06/10 00:04:15]

Done.

 
  private:
+  void OnSetupInProgressHandleDestroyed();
+
   DISALLOW_COPY_AND_ASSIGN(SyncService);
 };
 
 }  // namespace sync_driver
 
 #endif  // COMPONENTS_SYNC_DRIVER_SYNC_SERVICE_H_