Fix bug where mExtensions was not initialized.
Fix bug where mExtensions was not initialized.

Recent changes to mExtensions moved the initialization code from the
constructor to a separate function called load. Make sure to call
this function in the initExtensions function call.

Bug: 25615666

Change-Id: Ic016232c42afefd3b5bc3e4bd5c8428a11c454ad

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