[Sheriff] Revert "Check elimination temporarily disabled.", "Fix for buildbot failure after r19102.…

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 73348a6616828977432b128183487ad546baaff4..f757d20d9c7749d21d3daeed8784972b99db1728 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -2649,32 +2649,16 @@ class HCheckMaps V8_FINAL : public HTemplateInstruction<2> {
  public:
   static HCheckMaps* New(Zone* zone, HValue* context, HValue* value,
                          Handle<Map> map, CompilationInfo* info,
-                         HValue* typecheck = NULL);
+                         HValue *typecheck = NULL);
   static HCheckMaps* New(Zone* zone, HValue* context,
                          HValue* value, SmallMapList* maps,
-                         HValue* typecheck = NULL) {
+                         HValue *typecheck = NULL) {
     HCheckMaps* check_map = new(zone) HCheckMaps(value, zone, typecheck);
     for (int i = 0; i < maps->length(); i++) {
       check_map->Add(maps->at(i), zone);
     }
     return check_map;
   }
-  // HCheckMaps creation method safe for using during concurrent compilation
-  // (does not dereference maps handles).
-  static HCheckMaps* New(Zone* zone, HValue* context,
-                         HValue* value, UniqueSet<Map>* maps,
-                         HValue* typecheck,
-                         bool has_migration_target) {
-    HCheckMaps* check_map = new(zone) HCheckMaps(value, zone, typecheck);
-    for (int i = 0; i < maps->size(); i++) {
-      check_map->map_set_.Add(maps->at(i), zone);
-    }
-    if (has_migration_target) {
-      check_map->has_migration_target_ = true;
-      check_map->SetGVNFlag(kChangesNewSpacePromotion);
-    }
-    return check_map;
-  }
 
   bool CanOmitMapChecks() { return omit_; }
 
@@ -2687,7 +2671,6 @@ class HCheckMaps V8_FINAL : public HTemplateInstruction<2> {
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
 
   HValue* value() { return OperandAt(0); }
-  HValue* typecheck() { return OperandAt(1); }
 
   Unique<Map> first_map() const { return map_set_.at(0); }
   UniqueSet<Map> map_set() const { return map_set_; }