ART: Add getDeclaredConstructor cutout for unstarted runtime

In the vein of getDeclaredMethod and getDeclaredField. Refactor
code from java_lang_Class to share code.

Allows to compile-time initialize:
* sun.security.x509.AVAKeyword
* sun.security.x509.X500Name

Bug: 27265238

(cherry picked from commit f72f19fac0016499d33fd75b0463d0128a58a9f4)

Change-Id: I075c1b11f3408f5b31e4f84140a24fd8d3eaa17e
7 files changed