Add missing factory method for HDebugBreak.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 7d33141a4f61c150320d02aaceb2c74218506b66..7d3b879fb90bf79d46f47d07ca3b543aff71fc13 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -1303,6 +1303,8 @@ class HDeoptimize V8_FINAL : public HTemplateInstruction<0> {
 // Inserts an int3/stop break instruction for debugging purposes.
 class HDebugBreak V8_FINAL : public HTemplateInstruction<0> {
  public:
+  DECLARE_INSTRUCTION_FACTORY_P0(HDebugBreak);
+
   virtual Representation RequiredInputRepresentation(int index) V8_OVERRIDE {
     return Representation::None();
   }