Invoke AttachmentUploader and update AttachmentIds.

When GenericChangeProcessor calls AttachmentService::StoreAttachments
AttachmentService invokes AttachmentUploader to upload attachments.

When attachment gets uploaded AttachmentService invokes
AttachmentService::Delegate::OnAttachmentUploaded.

GenericChangeProcessor implements AttachmentService::Delegate for now.
When attachment is uploaded it call WriteTransaction to update entries
referring this attachment with new attachment id.

[email protected]
BUG=371629

Review URL: https://codereview.chromium.org/272043002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@271578 0039d316-1c4b-4281-b951-d872f2087c98
26 files changed