Revert r10118 from bleeding edge.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
===================================================================
--- src/hydrogen-instructions.h	(revision 10131)
+++ src/hydrogen-instructions.h	(working copy)
@@ -1271,7 +1271,12 @@
 
 class HStackCheck: public HTemplateInstruction<1> {
  public:
-  explicit HStackCheck(HValue* context) {
+  enum Type {
+    kFunctionEntry,
+    kBackwardsBranch
+  };
+
+  HStackCheck(HValue* context, Type type) : type_(type) {
     SetOperandAt(0, context);
   }
 
@@ -1289,7 +1294,13 @@
     }
   }
 
+  bool is_function_entry() { return type_ == kFunctionEntry; }
+  bool is_backwards_branch() { return type_ == kBackwardsBranch; }
+
   DECLARE_CONCRETE_INSTRUCTION(StackCheck)
+
+ private:
+  Type type_;
 };