[RESTRICT AUTOMERGE]:Modernize CTS/STS regex asserts.

New features include:
* regex timeout and warning
* printing what substring matched the pattern
* dump the tested string on test failure
* print the pattern string for the rest of the functions

These features help diagnose test failures and encourage better test
writing.

Test: $ sts-tradefed run sts-engbuild -m CtsSecurityBulletinHostTestCases
Bug: 122900866
Change-Id: I864c86ed16d1813aabac2ce245de5230502bce8e
2 files changed