tree f16d48a25e3b3f2026e78a9652be3122b680dd26
parent d8f32ea2dffd3f6a080b4eb55a11c0f1c6d7a3a6
author Andrew Lee <anwlee@google.com> 1422921029 -0800
committer Andrew Lee <anwlee@google.com> 1422922121 -0800

Null-protect attempt to get EmergencyButton.

Not all device layouts, such as for tablets, will have an Emergency
Button, so check for null before attempting to set a callback.

Bug: 18977746
Change-Id: I0e909e71c51f6923edda4707bb25053a5f2de398