Lambda indexOf() and has() were stricter than their function taking equivalents like find(), which allow a superclass of T to be passed as the function parameter type and not just the exact class T or a subclass thereof. This relaxes that restriction to be the same.
testing travis
Merge remote-tracking branch 'upstream/master' into lambda_strictness3
Merge commit 'cfa7a1c56237bdce6c713365a2c9c17d432b8957' into development