[turbofan] Add support for copy-on-write element stores.

src/code-factory.h

Index: src/code-factory.h
diff --git a/src/code-factory.h b/src/code-factory.h
index c0d2884325027d51a26c142c556eabfd7c854287..f9caf4dd6ed07c8b2a64503dac27a604a07dbfe3 100644
--- a/src/code-factory.h
+++ b/src/code-factory.h
@@ -136,6 +136,8 @@ class CodeFactory final {
   static Callable FastNewStrictArguments(Isolate* isolate,
                                          bool skip_stub_frame = false);
 
+  static Callable CopyFixedArray(Isolate* isolate);
+
   static Callable AllocateHeapNumber(Isolate* isolate);
 #define SIMD128_ALLOC(TYPE, Type, type, lane_count, lane_type) \
   static Callable Allocate##Type(Isolate* isolate);