Add android proguard rules for branch android8

[kraity]

Signed-off-by: Kraity kraity@krait.cn
(cherry picked from commit 1fccc2b)

What this PR does / why we need it?

Origin: #2511

Summary of your change

Please indicate you've done the following:

• Made sure tests are passing and test coverage is added if needed.
• Made sure commit message follow the rule of Conventional Commits specification.
• Considered the docs impact and opened a new docs issue or PR with docs changes if needed.