[turbofan] Switch JSForInPrepare to %ForInPrepare style.

src/compiler/typer.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/typer.h"
 
 #include "src/base/flags.h"
 #include "src/bootstrapper.h"
 #include "src/compilation-dependencies.h"
 #include "src/compiler/common-operator.h"
@@ skipping 632 matching lines @@
 
 Type* Typer::Visitor::TypeTypedStateValues(Node* node) {
   return Type::Internal(zone());
 }
 
 
 Type* Typer::Visitor::TypeCall(Node* node) { return Type::Any(); }
 
 
 Type* Typer::Visitor::TypeProjection(Node* node) {
+  // TODO(bmeurer): Make this beautiful! Use tuple type here.
+  if (node->InputAt(0)->opcode() == IrOpcode::kJSForInPrepare &&
+      ProjectionIndexOf(node->op()) == 2) {
+    return typer_->cache_.kSmi;
+  }
   // TODO(titzer): use the output type of the input to determine the bounds.
   return Type::Any();
 }
 
 
 Type* Typer::Visitor::TypeDead(Node* node) { return Type::Any(); }
 
 
 // JS comparison operators.
 
@@ skipping 1778 matching lines @@
   }
   if (Type::IsInteger(*value)) {
     return Type::Range(value->Number(), value->Number(), zone());
   }
   return Type::Constant(value, zone());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8