Ensure extract is seen as having scalar result.

Rationale:
Extracting from a vector yields a scalar, yet
our parallel mover and one DCHECK did not account
for that fact (note that moving towards a vector
type system will prevent such errors).

Regression test for this is part of the SAD CL.

Test: test-art-host test-art-target

Bug: 64091002
Change-Id: Id154edd1a069c54e7d8da069c368dea0a8f973f4
diff --git a/compiler/optimizing/ssa_liveness_analysis.cc b/compiler/optimizing/ssa_liveness_analysis.cc
index 185303b..754a762 100644
--- a/compiler/optimizing/ssa_liveness_analysis.cc
+++ b/compiler/optimizing/ssa_liveness_analysis.cc
@@ -474,7 +474,9 @@
   // For a SIMD operation, compute the number of needed spill slots.
   // TODO: do through vector type?
   HInstruction* definition = GetParent()->GetDefinedBy();
-  if (definition != nullptr && definition->IsVecOperation()) {
+  if (definition != nullptr &&
+      definition->IsVecOperation() &&
+      !definition->IsVecExtractScalar()) {
     return definition->AsVecOperation()->GetVectorNumberOfBytes() / kVRegSize;
   }
   // Return number of needed spill slots based on type.