ChromeOS: Accept NULL SystemBus in MediaTransferProtocolManager.

DBusThreadManager's GetSystemBus returns NULL if Chrome built for ChromeOS runs on Linux or in tests.

BUG=275286

Review URL: https://codereview.chromium.org/57333002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@233056 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 20 insertions, 83 deletions

diff --git a/device/media_transfer_protocol/media_transfer_protocol_daemon_client.cc b/device/media_transfer_protocol/media_transfer_protocol_daemon_client.cc
index 52e8e63..a65bf81 100644
--- a/device/media_transfer_protocol/media_transfer_protocol_daemon_client.cc
+++ b/device/media_transfer_protocol/media_transfer_protocol_daemon_client.cc
@@ -408,67 +408,6 @@ class MediaTransferProtocolDaemonClientImpl
   DISALLOW_COPY_AND_ASSIGN(MediaTransferProtocolDaemonClientImpl);
 };
 
-// A stub implementaion of MediaTransferProtocolDaemonClient.
-class MediaTransferProtocolDaemonClientStubImpl
-    : public MediaTransferProtocolDaemonClient {
- public:
-  MediaTransferProtocolDaemonClientStubImpl() {}
-  virtual ~MediaTransferProtocolDaemonClientStubImpl() {}
-
-  virtual void EnumerateStorages(
-      const EnumerateStoragesCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void GetStorageInfo(
-      const std::string& storage_name,
-      const GetStorageInfoCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void OpenStorage(const std::string& storage_name,
-                           const std::string& mode,
-                           const OpenStorageCallback& callback,
-                           const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void CloseStorage(const std::string& handle,
-                            const CloseStorageCallback& callback,
-                            const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void ReadDirectoryByPath(
-      const std::string& handle,
-      const std::string& path,
-      const ReadDirectoryCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void ReadDirectoryById(
-      const std::string& handle,
-      uint32 file_id,
-      const ReadDirectoryCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void ReadFileChunkByPath(
-      const std::string& handle,
-      const std::string& path,
-      uint32 offset,
-      uint32 length,
-      const ReadFileCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void ReadFileChunkById(
-      const std::string& handle,
-      uint32 file_id,
-      uint32 offset,
-      uint32 length,
-      const ReadFileCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void GetFileInfoByPath(
-      const std::string& handle,
-      const std::string& path,
-      const GetFileInfoCallback& callback,
-      const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void GetFileInfoById(const std::string& handle,
-                               uint32 file_id,
-                               const GetFileInfoCallback& callback,
-                               const ErrorCallback& error_callback) OVERRIDE {}
-  virtual void SetUpConnections(
-      const MTPStorageEventHandler& handler) OVERRIDE {}
-
- private:
-  DISALLOW_COPY_AND_ASSIGN(MediaTransferProtocolDaemonClientStubImpl);
-};
-
 }  // namespace
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -479,10 +418,8 @@ MediaTransferProtocolDaemonClient::MediaTransferProtocolDaemonClient() {}
 MediaTransferProtocolDaemonClient::~MediaTransferProtocolDaemonClient() {}
 
 // static
-MediaTransferProtocolDaemonClient*
-MediaTransferProtocolDaemonClient::Create(dbus::Bus* bus, bool is_stub) {
-  if (is_stub)
-    return new MediaTransferProtocolDaemonClientStubImpl();
+MediaTransferProtocolDaemonClient* MediaTransferProtocolDaemonClient::Create(
+    dbus::Bus* bus) {
   return new MediaTransferProtocolDaemonClientImpl(bus);
 }
 
diff --git a/device/media_transfer_protocol/media_transfer_protocol_daemon_client.h b/device/media_transfer_protocol/media_transfer_protocol_daemon_client.h
index bba9794..54400e1 100644
--- a/device/media_transfer_protocol/media_transfer_protocol_daemon_client.h
+++ b/device/media_transfer_protocol/media_transfer_protocol_daemon_client.h
@@ -163,9 +163,7 @@ class MediaTransferProtocolDaemonClient {
   virtual void SetUpConnections(const MTPStorageEventHandler& handler) = 0;
 
   // Factory function, creates a new instance and returns ownership.
-  // For normal usage, set |is_stub| to false.
-  static MediaTransferProtocolDaemonClient* Create(dbus::Bus* bus,
-                                                   bool is_stub);
+  static MediaTransferProtocolDaemonClient* Create(dbus::Bus* bus);
 
  protected:
   // Create() should be used instead.
diff --git a/device/media_transfer_protocol/media_transfer_protocol_manager.cc b/device/media_transfer_protocol/media_transfer_protocol_manager.cc
index 6c0210a..222dd10 100644
--- a/device/media_transfer_protocol/media_transfer_protocol_manager.cc
+++ b/device/media_transfer_protocol/media_transfer_protocol_manager.cc
@@ -50,23 +50,27 @@ class MediaTransferProtocolManagerImpl : public MediaTransferProtocolManager {
     session_bus_ = new dbus::Bus(options);
 #endif
 
-    // Listen for future mtpd service owner changes, in case it is not
-    // available right now. There is no guarantee on Linux or ChromeOS that
-    // mtpd is running already.
-    mtpd_owner_changed_callback_ =
-        base::Bind(&MediaTransferProtocolManagerImpl::FinishSetupOnOriginThread,
-                   weak_ptr_factory_.GetWeakPtr());
-    GetBus()->ListenForServiceOwnerChange(mtpd::kMtpdServiceName,
-                                          mtpd_owner_changed_callback_);
-    GetBus()->GetServiceOwner(mtpd::kMtpdServiceName,
-                              mtpd_owner_changed_callback_);
+    if (GetBus()) {
+      // Listen for future mtpd service owner changes, in case it is not
+      // available right now. There is no guarantee on Linux or ChromeOS that
+      // mtpd is running already.
+      mtpd_owner_changed_callback_ = base::Bind(
+          &MediaTransferProtocolManagerImpl::FinishSetupOnOriginThread,
+          weak_ptr_factory_.GetWeakPtr());
+      GetBus()->ListenForServiceOwnerChange(mtpd::kMtpdServiceName,
+                                            mtpd_owner_changed_callback_);
+      GetBus()->GetServiceOwner(mtpd::kMtpdServiceName,
+                                mtpd_owner_changed_callback_);
+    }
   }
 
   virtual ~MediaTransferProtocolManagerImpl() {
     DCHECK(g_media_transfer_protocol_manager);
     g_media_transfer_protocol_manager = NULL;
-    GetBus()->UnlistenForServiceOwnerChange(mtpd::kMtpdServiceName,
-                                            mtpd_owner_changed_callback_);
+    if (GetBus()) {
+      GetBus()->UnlistenForServiceOwnerChange(mtpd::kMtpdServiceName,
+                                              mtpd_owner_changed_callback_);
+    }
 
 #if !defined(OS_CHROMEOS)
     session_bus_->GetDBusTaskRunner()->PostTask(
@@ -428,9 +432,7 @@ class MediaTransferProtocolManagerImpl : public MediaTransferProtocolManager {
 
     current_mtpd_owner_ = mtpd_service_owner;
 
-    mtp_client_.reset(
-        MediaTransferProtocolDaemonClient::Create(GetBus(),
-                                                  false /* not stub */));
+    mtp_client_.reset(MediaTransferProtocolDaemonClient::Create(GetBus()));
 
     // Set up signals and start initializing |storage_info_map_|.
     mtp_client_->SetUpConnections(