Add flag polymorphic_with_deopt (default true) and handle case when false: use megamorphic instead …

runtime/vm/flow_graph_compiler.h

Index: runtime/vm/flow_graph_compiler.h
diff --git a/runtime/vm/flow_graph_compiler.h b/runtime/vm/flow_graph_compiler.h
index 4b7f4c71d02d806b5cbae030eb2c2a11f3a88a4a..17b2612f0f98ec44f182135225141d2af8399ae5 100644
--- a/runtime/vm/flow_graph_compiler.h
+++ b/runtime/vm/flow_graph_compiler.h
@@ -407,6 +407,13 @@ class FlowGraphCompiler : public ValueObject {
                         intptr_t token_pos,
                         LocationSummary* locs);
 
+  void EmitPolymorphicInstanceCall(const ICData& ic_data,
+                                   intptr_t argument_count,
+                                   const Array& argument_names,
+                                   intptr_t deopt_id,
+                                   intptr_t token_pos,
+                                   LocationSummary* locs);
+
   void EmitMegamorphicInstanceCall(const ICData& ic_data,
                                    intptr_t argument_count,
                                    intptr_t deopt_id,