[sil] Add a run of ownership model eliminator in the lowering pass pipeline to ensure we eliminate ownership even if a bisecting counter has disabled the normal ome run.

I also had to fix up one test and eliminated a test that did not really make
sense in the first place to test with ossa. (Specifically,
copy_value_destroy_value is a test I added when adding copy_value,
destroy_value, it really doesn't make sense since we will just lower it to
retain, release before we hit IRGen).

Author: gottesmm

lib/SILOptimizer/PassManager/PassPipeline.cpp

@@ -575,6 +575,7 @@ SILPassPipelinePlan
 SILPassPipelinePlan::getLoweringPassPipeline(const SILOptions &Options) {
   SILPassPipelinePlan P(Options);
   P.startPipeline("Address Lowering");
+  P.addOwnershipModelEliminator();
   P.addIRGenPrepare();
   P.addAddressLowering();
 

test/IRGen/copy_value_destroy_value.sil

@@ -10,6 +10,9 @@ entry(%x : @guaranteed $Builtin.AnyObject):
   // CHECK-native: swift_retain
   // CHECK-objc: swift_unknownObjectRetain
   %y = copy_value %x : $Builtin.AnyObject
+  br bb1
+
+bb1:
   // CHECK-native: swift_release
   // CHECK-objc: swift_unknownObjectRelease
   destroy_value %y : $Builtin.AnyObject