Avoid throwing ISE in Canvas#restore underflow
Avoid throwing ISE in Canvas#restore underflow

bug:19829784

Change-Id: I5829a7783ad912c09c83dee17bad10b90f42aace

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