Keep track of which attachments are referenced by which sync entries.

Keep track of which attachments are referenced by which sync entries.

Relanding https://codereview.chromium.org/247983002/ after fixing
memory leak.

PutAttachmentMetadata on MutableEntry now notifies the Directory when
the attachments associated with an entry change.

Give Directory::InitializeIndices a ScopedKernelLock to be consistent
and make it easier to ensure we are locking when we need to.

GenericChangeProcess passes new attachments to AttachmentService for
storage and upload.

Add an output parameter to GenericChangeProcessor's HandleActionAdd and
HandleActionUpdate methods so they can keep track of potentially new
attachments and pass them to AttachmentService for storage/upload.

Convert AttachmentService's OnSyncDataAdd to StoreAttachments.

Implement HasAttachmentNotOnServer.

BUG=348625, 353303, 354530, 356266
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=267887

[maniscalco, 2014-05-02 00:30:38]

Pavel, would you please review this change?  You previously reviewed
https://codereview.chromium.org/247983002/, which I reverted because it
introduced a memory leak.  This change is identical, except for the memory leak.
 Check out the diff between patch set 1 and 2.

[maniscalco, 2014-05-02 00:33:21]

On 2014/05/02 00:30:38, maniscalco wrote:
> Pavel, would you please review this change?  You previously reviewed
> https://codereview.chromium.org/247983002/, which I reverted because it
> introduced a memory leak.  This change is identical, except for the memory
leak.
>  Check out the diff between patch set 1 and 2.

Added pavely as reviewer.

[pavely, 2014-05-02 16:34:45]

lgtm

[maniscalco, 2014-05-02 17:32:48]

The CQ bit was checked by maniscalco@chromium.org

[commit-bot: I haz the power, 2014-05-02 17:33:16]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/maniscalco@chromium.org/264793007/20001

[commit-bot: I haz the power, 2014-05-02 19:00:12]

Change committed as 267887