VM: Fix receiver type propagation in presence of try-catch.

runtime/vm/flow_graph.h

Index: runtime/vm/flow_graph.h
diff --git a/runtime/vm/flow_graph.h b/runtime/vm/flow_graph.h
index d4d9d2fa8e4b4b057fa12c80ca50662390728ade..992ab519fb5762b51ab99ce67abff1f6e4b035d5 100644
--- a/runtime/vm/flow_graph.h
+++ b/runtime/vm/flow_graph.h
@@ -159,6 +159,9 @@ class FlowGraph : public ZoneAllocated {
     return current_ssa_temp_index();
   }
 
+  bool InstanceCallNeedsClassCheck(InstanceCallInstr* call,
+                                   RawFunction::Kind kind) const;
+
   Thread* thread() const { return thread_; }
   Zone* zone() const { return thread()->zone(); }
   Isolate* isolate() const { return thread()->isolate(); }
@@ -352,6 +355,9 @@ class FlowGraph : public ZoneAllocated {
                         Value* use,
                         bool is_environment_use);
 
+  bool IsReceiver(Definition* def) const;
+  void ComputeIsReceiverRecursive(PhiInstr* phi, BitVector* processed) const;
+
   Thread* thread_;
 
   // DiscoverBlocks computes parent_ and assigned_vars_ which are then used