Dont invoke getInstallLocation for forward locked apps.
If INSTALL_ON_SDCARD is selected as default, forward locked
apps are not being installed because of conflicting flags.
Although not strictly a published API (the class does not appear in the docs), it has found it's way into the API through
the public, subclassable android.webkit.JsResult class where it is a protected member.
Based on changed from Ben.
There's no need to have constants like OP_UNUSED_FF in the API. They
serve no purpose, and it makes life confusing when an opcode is defined
(does the "unused" one go away, breaking the API? do we have the real
definition and the "unused" definition simultaneously?).
Discussed / approved by API council.
