[Android] Provide the advice to user for compressor.

This patch is to provide the advice to user when the option value is wrong.
In prior version, the packaging process will not be terminated when the
option value for compressor is wrong.
Now verify the option value, if it is not in the valid list, provide the
advice to user to refine the option.

BUG=XWALK-1672
The parentheses are not needed.