[turbofan] Introduce JSToInteger and JSToLength operators.

src/compiler/js-typed-lowering.h

Index: src/compiler/js-typed-lowering.h
diff --git a/src/compiler/js-typed-lowering.h b/src/compiler/js-typed-lowering.h
index 4621a45e283bde4fdd8e85dad83b3cbd32ea484a..151787106b2b1227e75a9c6fb5fe7ab064e05cdb 100644
--- a/src/compiler/js-typed-lowering.h
+++ b/src/compiler/js-typed-lowering.h
@@ -62,6 +62,8 @@ class JSTypedLowering final : public AdvancedReducer {
   Reduction ReduceJSEqual(Node* node, bool invert);
   Reduction ReduceJSStrictEqual(Node* node, bool invert);
   Reduction ReduceJSToBoolean(Node* node);
+  Reduction ReduceJSToInteger(Node* node);
+  Reduction ReduceJSToLength(Node* node);
   Reduction ReduceJSToNumberInput(Node* input);
   Reduction ReduceJSToNumber(Node* node);
   Reduction ReduceJSToStringInput(Node* input);