Revert "cleanup from last revert"

This reverts commit a132ad0279a07df5336d62aead5a804b643d01c9.
Revert "Revert "Frameworks: Port hardware key rebinding""

This reverts commit f2b54eedeb7638eccb05f3b3b6c720e23154f0f2.

Conflicts:
	core/java/android/provider/Settings.java

Change-Id: I2cc13591122fa53bd7a9da2067fa7e90cd2cab08