ART: Use dex2oat watchdog in host run-test

Increase the timeout time for dex2oat to 90s, but let the internal
watchdog trigger after the original 60s.

Bug: 62337922
Test: art/test/testrunner/testrunner.py -b --host
Change-Id: I4ef72c62be56b4de2d872cb387660ac1d8244e1a