update SystemUI's proguard.flags

Change-Id: I5aa73eddd3fea6cddeddaf94e202d8de870e7df5
Clean up unnecessary backslashes

* Last line in a PRODUCT_COPY_FILES block shouldn't end with backslash

Change-Id: I57b4914048a2a17ff98057844941898b682dbcd5
Ignore null stylus gesture settings

If the user performs a stylus gesture that has not been configured in
the settings at all, the gesture filter would incorrectly interpret the
setting's null value as an app launch action.

Change-Id: If7f600a688bb7b5e0a9a2e912c3d6183a9c9a69e
Sync Merge remote-tracking branch 'upstream/cm-10.1' into cm-10.1