Set fit insets type for decor insets test am: 614ed9e0 am: 43e2a2b2

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23468179



Change-Id: I5ddb88a333d79114e377a15432f144e5dcbaf7f4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>