Disallow attaching files from our own EmailAttachmentProvider.

This is to backport a security fix reported in b/71814449 and
b/72569023. Fix is using the same approach as b/27308057, which is to
prevent Compose from accepting URIs with our own email attachment

Bug: b/71814449
Change-Id: Ib9df21648d00d2ef2da9fac05cc39fee253de8e2
(cherry picked from commit 7227751994624bdb2ba958714cc861b8bab41634)
1 file changed