Remove HOST_ARCH as filtering condition

Now we support x86_64 as HOST_ARCH as well.

Change-Id: I73f89670f02a83f4c631cdb37159987632c8717d
Merge "Remove HOST_ARCH as filtering condition"
am d68086be: Merge "Remove HOST_ARCH as filtering condition"

* commit 'd68086becbc77708343c5415a8da483db2bd8ae0':
  Remove HOST_ARCH as filtering condition
Update makefiles for clang host builds. DO NOT MERGE

bug 16172793

Change-Id: If7484c5dbcccce7d925bec97bff0a3e4c30e9434
Remove bad gcc flag for Darwin.  DO NOT MERGE

gcc can't handle the -Wno-int-conversion, so we need to remove this
condition for Darwin and replace it with the appropriate
LOCAL_CLANG := false

Change-Id: I9a2861535d865f447014b1fce353b86feea90d22