Remove category checking from incompatible changes.

String categories are deprecated, replace this special-cased value with a specific OptionMetadata tag, TRIGGERED_BY_ALL_INCOMPATIBLE_CHANGES.

RELNOTES: None.
PiperOrigin-RevId: 191069412
GitOrigin-RevId: 78a5fcff8a311c71cfe163a40856f7413e346409
Change-Id: I1be6e8a8c592e0fa8ec29a631957d840f34a2113
3 files changed
tree: 8f6e5fe48848bea0a88762d3ee4c3a24409e2e61
  1. java/
  2. test/