am 4a1c70e5: Switch the required host Java environment to 1.6.

Merge commit '4a1c70e53be40fd1b2c14eb7c0acc93f6df865bc' into gingerbread-plus-aosp

* commit '4a1c70e53be40fd1b2c14eb7c0acc93f6df865bc':
  Switch the required host Java environment to 1.6.