Revert "Revert "Implement long negate instruction in the optimizing compiler.""

This reverts commit 30ca3d847fe72cfa33e1b2473100ea2d8bea4517.

Change-Id: I188ca8d460d55d3a9966bcf31e0588575afa77d2
diff --git a/compiler/optimizing/builder.cc b/compiler/optimizing/builder.cc
index 79cbd0e..0ab7782 100644
--- a/compiler/optimizing/builder.cc
+++ b/compiler/optimizing/builder.cc
@@ -748,6 +748,11 @@
       break;
     }
 
+    case Instruction::NEG_LONG: {
+      Unop_12x<HNeg>(instruction, Primitive::kPrimLong);
+      break;
+    }
+
     case Instruction::NOT_INT: {
       Unop_12x<HNot>(instruction, Primitive::kPrimInt);
       break;