Do not report app bound differences as a Configuration change.

App bounds are an internal Configuration field and should not
influence the diff that determines whether the Configuration has
changed. This changelist ensures this by introducing a new flag that
is identified server side and filtered before informing the client
that the configuration has changed.

Change-Id: Ibf1387f73eaa9b39e6213e1a1109c4cd57554e7c
Fixes: 63927944
Test: bit FrameworksServicesTests:com.android.server.wm.AppBoundsTests#testAppBoundsConfigurationDiff
Test: go/wm-smoke