Fix JSR-166 tests.

- Remove calls to setSecurityManager, which throws unconditionally
  on android.
- Remove an unsupported AccessController check.
- Remove an assertion that the default uncaught exception handler is
  null. Regular android processes always have one installed.

bug: 20628776

(cherry picked from commit 151f344e88956741c0b8e4018df845d85d4eef25)

Change-Id: Ida7499c74586d007b8381522bec45f9a0c8fa7b4
3 files changed