Check if mmp's encoded subject is null before used

From AOSP:
  https://android-review.googlesource.com/#/c/57709/1

Change-Id: I1de3c83b2b68128f725f8bbaf3d6764b2bdf836b
Signed-off-by: Roger Chen <cxr514033970@gmail.com>
Mms : refactor translations

Patch set 2 : correction
Patch set 3 : correction
Patch set 4 : correction

Change-Id: I9cbfc102b8bc1dd9b165a5097df2e614106bd385
Mms: Add missing AF Translations

Change-Id: I002bb71609fe9aaa32416f26aff0229d947c5ad2
Mms: AF translations

Change-Id: I4d314dab1db064da002efe448b49123d76dacfa9
Mms: Simplified Chinese Translations

Updated translations, fixed file permissions, and sync'd strings.xml
to AOSP master.

Change-Id: I5fe5c974b04670fc5763e866921df278f90e245a
Update German translation

Change-Id: I4b61bfa8d1b7c670a59946830bbcf39f5721c7a0
Merge "Update German translation" into cm-10.1
Mms: NB translation

PS2: Trying to make Cid happy!

Commit for staging: http://review.cyanogenmod.org/#/c/37277/

Change-Id: I8bc2745f93f3c88ce4530e24299040efc637f4de
Merge "Mms: Simplified Chinese Translations" into cm-10.1
MMS: Update Polish translation

Merging

Change-Id: If26f73ac7fbb0333aa1358f841c3dc874793c2a5
Merge "MMS: Update Polish translation" into cm-10.1
Merge remote-tracking branch 'cm/cm-10.1' into jb-mr1