This bug and AOSP patch arrived last July. Supposedly, I
merged the change, but it's certainly not fixed in bugler, nor in various
copies of PduPersister in Android's master. Fixing all the locations
now.

Test: manual - sent/received MMS's to verify the change didn't break
existing behavior.

Bug: 22851197
Change-Id: Ia79bd9951b1820ebc42baf0eef38667753d77ab9