Don't crash in AppBarLayout inflation

Specific attributes used in AppBarLayout's theme will cause
the super constructor to call onCreateDrawableState before
class-level fields are initialized. Move the creation of temp
array to be on-demand.

Bug: 37460722
Test: ./gradlew support-design:connectedCheck --info --daemon -Pandroid.testInstrumentationRunnerArguments.class=android.support.design.widget.AppBarWithScrollbarsTest
Change-Id: I086f25c676201876fd76cd3684afcab7e09436d0
6 files changed