Move InputFeature flag definitions to AIDL (1/2)

We convert the InputFeatures flags into AIDL enums that will have values
generated in both native and java code so that the value only has to be
defined once.

Bug: 162194035
Test: build, presubmit
Change-Id: I28bd51a4affe705155c08c273a902d86665c63b9
3 files changed