Implement int negate instruction in the optimizing compiler.

- Add support for the neg-int (integer two's complement
  negate) instruction in the optimizing compiler.
- Add a HNeg node type for control-flow graphs and an
  intermediate HUnaryOperation base class.
- Generate ARM, x86 and x86-64 code for integer HNeg nodes.

Change-Id: I72fd3e1e5311a75c38a8cb665a9211a20325a42e
diff --git a/compiler/optimizing/builder.h b/compiler/optimizing/builder.h
index e68cdb0..90e50ad 100644
--- a/compiler/optimizing/builder.h
+++ b/compiler/optimizing/builder.h
@@ -95,6 +95,9 @@
   bool InitializeParameters(uint16_t number_of_parameters);
 
   template<typename T>
+  void Unop_12x(const Instruction& instruction, Primitive::Type type);
+
+  template<typename T>
   void Binop_23x(const Instruction& instruction, Primitive::Type type);
 
   template<typename T>