[builtins] Add support for JS builtins written in TurboFan.

src/compiler/js-intrinsic-lowering.cc

Index: src/compiler/js-intrinsic-lowering.cc
diff --git a/src/compiler/js-intrinsic-lowering.cc b/src/compiler/js-intrinsic-lowering.cc
index c4a4f53581fd8fbe806a06dd302fbc235945d975..ac882f71147df2d7505efc323f1e85d5252143d8 100644
--- a/src/compiler/js-intrinsic-lowering.cc
+++ b/src/compiler/js-intrinsic-lowering.cc
@@ -59,8 +59,6 @@ Reduction JSIntrinsicLowering::Reduce(Node* node) {
       return ReduceMathClz32(node);
     case Runtime::kInlineMathFloor:
       return ReduceMathFloor(node);
-    case Runtime::kInlineMathSqrt:
-      return ReduceMathSqrt(node);
     case Runtime::kInlineValueOf:
       return ReduceValueOf(node);
     case Runtime::kInlineFixedArrayGet:
@@ -224,15 +222,6 @@ Reduction JSIntrinsicLowering::ReduceMathFloor(Node* node) {
 }
 
 
-Reduction JSIntrinsicLowering::ReduceMathSqrt(Node* node) {
-  // Tell the compiler to assume number input.
-  Node* renamed = graph()->NewNode(common()->Guard(Type::Number()),
-                                   node->InputAt(0), graph()->start());
-  node->ReplaceInput(0, renamed);
-  return Change(node, machine()->Float64Sqrt());
-}
-
-
 Reduction JSIntrinsicLowering::ReduceValueOf(Node* node) {
   // if (%_IsSmi(value)) {
   //   return value;