VM: Remove unecessary dead code from flow-graph builder.

runtime/vm/intermediate_language.cc

Index: runtime/vm/intermediate_language.cc
diff --git a/runtime/vm/intermediate_language.cc b/runtime/vm/intermediate_language.cc
index a390ed6b658279ac1c63f0a6fa8f36811741f138..20b876e0257912444917573344e6ea6782e93a80 100644
--- a/runtime/vm/intermediate_language.cc
+++ b/runtime/vm/intermediate_language.cc
@@ -2027,9 +2027,6 @@ Definition* LoadFieldInstr::Canonicalize(FlowGraph* flow_graph) {
         IsFixedLengthArrayCid(call->Type()->ToCid())) {
       return call->ArgumentAt(1);
     }
-    if (call->is_native_list_factory()) {
-      return call->ArgumentAt(0);
-    }
   }
 
   CreateArrayInstr* create_array =
@@ -2666,9 +2663,6 @@ Instruction* GuardFieldLengthInstr::Canonicalize(FlowGraph* flow_graph) {
       LoadFieldInstr::IsFixedLengthArrayCid(call->Type()->ToCid())) {
     length = call->ArgumentAt(1)->AsConstant();
   }
-  if (call->is_native_list_factory()) {
-    length = call->ArgumentAt(0)->AsConstant();
-  }
   if ((length != NULL) &&
       length->value().IsSmi() &&
       Smi::Cast(length->value()).Value() == expected_length) {