Remove SystemApi annotations.
Remove SystemApi annotations.

SystemApi only makes sense for hidden APIs.

Bug: 18097290
Change-Id: I76af5f54321c4010334ef419bb7e066663ec784c

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base