Drive: Mount/Unmount GoogleDrive on Files App when the file system is mounted/unmounted.

chrome/browser/chromeos/gdata/gdata_file_system.cc

Index: chrome/browser/chromeos/gdata/gdata_file_system.cc
diff --git a/chrome/browser/chromeos/gdata/gdata_file_system.cc b/chrome/browser/chromeos/gdata/gdata_file_system.cc
index 949ca502c72fbfceca97db5ae5b43830ffc99bac..8450e3208e5a15edc9ad55f9548af8b077fac0cb 100644
--- a/chrome/browser/chromeos/gdata/gdata_file_system.cc
+++ b/chrome/browser/chromeos/gdata/gdata_file_system.cc
@@ -849,9 +849,16 @@ void GDataFileSystem::StartUpdates() {
 }
 
 void GDataFileSystem::StopUpdates() {
+  // If unmount request comes from filesystem side, this method may be called
+  // twice. First is just after unmounting on filesystem, second is after
+  // unmounting on filemanager on JS. In other words, if this is called from
+  // GDataSystemService::RemoveDriveMountPoint(), this will be called again from
+  // FileBrowserEventRouter::HandleRemoteUpdateRequestOnUIThread().
+  // We choose to stopping updates asynchronous without waiting for filemanager,
+  // rather than waiting for completion of unmounting on filemanager.
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  DCHECK(update_timer_.IsRunning());
-  update_timer_.Stop();
+  if (update_timer_.IsRunning())
+    update_timer_.Stop();
 }
 
 void GDataFileSystem::GetEntryInfoByResourceId(
@@ -3382,6 +3389,24 @@ void GDataFileSystem::RemoveStaleEntryOnUpload(const std::string& resource_id,
   }
 }
 
+void GDataFileSystem::NotifyFileSystemMounted() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  DVLOG(1) << "File System is mounted";
+  // Notify the observers that the file system is mounted.
+  FOR_EACH_OBSERVER(GDataFileSystemInterface::Observer, observers_,
+                    OnFileSystemMounted());
+}
+
+void GDataFileSystem::NotifyFileSystemUnmounting() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+
+  DVLOG(1) << "File System is getting unmounted";
+  // Notify the observers that the file system is getting unmounted.
+  FOR_EACH_OBSERVER(GDataFileSystemInterface::Observer, observers_,
+                    OnFileSystemUnmounting());
+}
+
 void GDataFileSystem::RunAndNotifyInitialLoadFinished(
     const FindEntryCallback& callback,
     GDataFileError error,