Added Java Language methods for blastula management.

This commit adds Java Language wrappers for native blastula management
functions.  No changes are made to the application lifecycle.

Topic: zygote-prefork
Test: make & flash & launch apps & check log for messages
Bug: 68253328
Change-Id: Ie9fd0aea2952dbd3baaca22c820e9af700f5e89d