Disable runtime hidden API checks in signature tests

Signature tests require access to hidden methods through reflection to
ensure that the runtime representation and API specifications are
compatible. Enabling the hidden api checks which prevent hidden methods
from being accessed through reflection prevented those tests from
finding potential compatibility issues.

This change disables the hidden api checks to correct that. That will
cause CTS signature tests to start failing as some potential
compatibility issues have been introduced since hidden api checks were
enabled by default. A separate change will update the allow list to
fix the test failure.

Bug: 171459260
Test: atest CtsApacheHttpLegacy27ApiSignatureTestCases
Change-Id: I8a744098346ce1cfae7ff4d7a2eca3619296f321
10 files changed