Optimize TypedData operators [] and []= in the same way as ScalarList.

runtime/vm/flow_graph_compiler.h

Index: runtime/vm/flow_graph_compiler.h
===================================================================
--- runtime/vm/flow_graph_compiler.h	(revision 19943)
+++ runtime/vm/flow_graph_compiler.h	(working copy)
@@ -414,12 +414,10 @@
                                                 intptr_t index_scale,
                                                 Register array,
                                                 Register index);
-  static Address ExternalElementAddressForIntIndex(intptr_t cid,
-                                                   intptr_t index_scale,
+  static Address ExternalElementAddressForIntIndex(intptr_t index_scale,
                                                    Register array,
                                                    intptr_t offset);
-  static Address ExternalElementAddressForRegIndex(intptr_t cid,
-                                                   intptr_t index_scale,
+  static Address ExternalElementAddressForRegIndex(intptr_t index_scale,
                                                    Register array,
                                                    Register index);