Disable the following assertion in parse1.cpp temporarily, to reduce noise in the testing pipelines while the root cause of its failures is investigated in JDK-8305185:

assert(false) failed: Can't determine return type.

This assertion was added by JDK-8303951 to force the re-evaluation of compilation bailouts. The invariant violation it catches is harmless (other than potentially causing a performance degradation) because it leads to a compilation bailout.