Clean up Class::GetDirectInterface().

Fetch array interfaces from the `IfTable`. This removes the
only use of the `Thread* self` argument, so we can remove
that argument. We also make the function non-static to avoid
the explicit `klass` argument. Similarly clean up arguments
of `Class::FindClass()` and `Class::FindStaticClass()`.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 181943478
Change-Id: Id639b675b4eb331a777cf318eb61bd19e05de4f0
10 files changed