Revert "Revert "Ensure dex file are extracted and verified at load time""

The issue was caused by running device-gtests as root (which will always
have full write access everywhere).

For now, disable the tests that rely on file permissions when running as
root.

Test: m test-art-target-gtest-oat_file_assistant_test
Bug: 36605597
Bug: 36824842

This reverts commit 9bfc6bb1.

Change-Id: I60e8c3d602ca40b1f1e12e8808055effcbb8dcc6