Revert "Support for narrow operands in "dangerous" operations."

Fails on armv8 / speed-profile

This reverts commit 636e870d55c1739e2318c2180fac349683dbfa97.

Change-Id: Ib2a09b3adeba994c6b095672a1e08b32d3871872
diff --git a/compiler/optimizing/loop_optimization.h b/compiler/optimizing/loop_optimization.h
index 35298d4..6d5978d 100644
--- a/compiler/optimizing/loop_optimization.h
+++ b/compiler/optimizing/loop_optimization.h
@@ -137,11 +137,7 @@
                       HInstruction* opa,
                       HInstruction* opb,
                       Primitive::Type type);
-  void GenerateVecOp(HInstruction* org,
-                     HInstruction* opa,
-                     HInstruction* opb,
-                     Primitive::Type type,
-                     bool is_unsigned = false);
+  void GenerateVecOp(HInstruction* org, HInstruction* opa, HInstruction* opb, Primitive::Type type);
 
   // Vectorization idioms.
   bool VectorizeHalvingAddIdiom(LoopNode* node,