tree 3d2ccceb8204fee261f5a595a61a23d35b6f8ef3
parent 28e37c0d9a643d4d7a33195fdee6da5a0ab9d206
author srawlins <srawlins@google.com> 1591739741 -0400
committer Sam Rawlins <sam.rawlins@gmail.com> 1594309593 -0700

MockBuilder: catch when users try to mock an un-subtypable class.

The Dart language forbids mocking these classes, so any test would fail to run.

PiperOrigin-RevId: 315566299