tree 97f8d588be7e92803bfe45e1526117865569607a
parent a96501cff3ca998bb705b49feede6af28a53189d
author Ta-wei Yen <twyen@google.com> 1468372719 -0700
committer Ta-wei Yen <twyen@google.com> 1468372719 -0700

Implement VVM Task Scheduling

Before CL multiple activate events will be fired during boot and each
one of them will be processed, which is redundant. The activation will
also trigger multiple sync events. During the initial download of
multiple voicemails an upload will also be trigger for each voicemail.
The flood of connections is know to have the client banned by the
server. Codes exists for retrying, but does not actually do anything.

In this CL TaskSchedulerService is implemented which will prevent
duplicated tasks from being queued, throttle requests, and handle
retries.

"Activate" event is not in scheduling yet.

- OmtpVvmSyncService is no longer a service. It will be renamed later.
  It can now be called to sync voicemail in a single threaded manner.

Fixes: 28729940
Bug: 28730056

Change-Id: I3678d8a16326e9a181bb401c003574928f02ae00