Remove illegal characters from EAS 2.5 attachment file names

* For some reason, EAS 2.5 sends us partially encoded file names,
  which we use to specify attachments to be loaded.
* It turns out that these file names aren't properly encoded for
  EAS's use in the GetAttachment command; some additional characters
  must be escaped using %nn.
* We now check for EAS 2.5 and escape illegal characters

Bug: 5341416
Change-Id: Ie112359e139581c8ae31e40869b2fa0e568d7f65
3 files changed