[Android] Add core case for cookie manager.
This test covers the basic features of cookies, including:
1. AcceptFileSchemeCookies
2. AcceptCookie
3. RemoveAllCookies
4. CookieExpiration

Steps for test:
1. install XWalkCoreShell.apk
2. python build/android/test_runner.py instrumentation \
--release --test-apk=XWalkCoreTest --test_data \
xwalkview:xwalk/test/data/device_files/  --verbose \
-f CookieManagerTest