Implement InstanceIDAndroid using InstanceIDWithSubtype.java

Replaces the previous stub implementation with a fully functional
implementation backed by InstanceIDWithSubtype.java.

Part of a series of patches:
1. https://codereview.chromium.org/1832833002 adds InstanceIDWithSubtype
2. this patch
3. https://codereview.chromium.org/1829023002 adds fake and test
4. https://codereview.chromium.org/1854093002 enables InstanceID by default
5. https://codereview.chromium.org/1851423003 switches Push to InstanceIDs

BUG=589461

Review URL: https://codereview.chromium.org/1830983002

Cr-Commit-Position: refs/heads/master@{#387646}
21 files changed