Merge "Revert "Error if $(LOCAL_PATH) is empty""

## Common instructions for a generic module.

###########################################################

LOCAL_PATH := $(strip $(LOCAL_PATH))

ifeq ($(LOCAL_PATH),)

  $(error LOCAL_PATH is not defined)

endif

LOCAL_MODULE := $(strip $(LOCAL_MODULE))

ifeq ($(LOCAL_MODULE),)

  $(error $(LOCAL_PATH): LOCAL_MODULE is not defined)