Use java.util.Objects.hashCode to get hashcode.

Cherry-picked cleanly from:
https://android-review.git.corp.google.com/#/c/415268/

Test: Telephony sanity tests

Merged-in: I8b845f2e5e44b242278b8955807d1b40e67e1414
Change-Id: I8b845f2e5e44b242278b8955807d1b40e67e1414
(cherry picked from commit 26439f5616be0f7894ed37e6952b3a6841d3b164)
1 file changed