Fix corner cases of type inference with implicit references to `.call`.

pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart

 // Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// This file declares a "shadow hierarchy" of concrete classes which extend
 /// the kernel class hierarchy, adding methods and fields needed by the
 /// BodyBuilder.
 ///
 /// Instances of these classes may be created using the factory methods in
 /// `ast_factory.dart`.
@@ skipping 1016 matching lines @@
         ? new InterfaceType(mapClass, [inferredKeyType, inferredValueType])
         : null;
     inferrer.listener.mapLiteralExit(this, inferredType);
     return inferredType;
   }
 }
 
 /// Shadow object for [MethodInvocation].
 class KernelMethodInvocation extends MethodInvocation
     implements KernelExpression {
+  /// Indicates whether this method invocation is a call to a `call` method
+  /// resulting from the invocation of a function expression.
+  final bool _isImplicitCall;
+
   KernelMethodInvocation(Expression receiver, Name name, Arguments arguments,
-      [Procedure interfaceTarget])
-      : super(receiver, name, arguments, interfaceTarget);
-
-  KernelMethodInvocation.byReference(Expression receiver, Name name,
-      Arguments arguments, Reference interfaceTargetReference)
-      : super.byReference(receiver, name, arguments, interfaceTargetReference);
+      {bool isImplicitCall: false, Procedure interfaceTarget})
+      : _isImplicitCall = isImplicitCall,
+        super(receiver, name, arguments, interfaceTarget);
 
   @override
   void _collectDependencies(KernelDependencyCollector collector) {
     // The inference dependencies are the inference dependencies of the
     // receiver.
     collector.collectDependencies(receiver);
   }
 
   @override
   DartType _inferExpression(
@@ skipping 20 matching lines @@
         // https://codereview.chromium.org/2923653003/.
         if (interfaceMember is Procedure) {
           interfaceTarget = interfaceMember;
         }
       }
       if (interfaceMember is Procedure) {
         isOverloadedArithmeticOperator = inferrer.typeSchemaEnvironment
             .isOverloadedArithmeticOperator(interfaceMember);
       }
     }
-    var calleeType =
-        inferrer.getCalleeFunctionType(interfaceMember, receiverType, name);
+    var calleeType = inferrer.getCalleeFunctionType(
+        interfaceMember, receiverType, name, !_isImplicitCall);
     var inferredType = inferrer.inferInvocation(typeContext, typeNeeded,
         fileOffset, calleeType, calleeType.returnType, arguments,
         isOverloadedArithmeticOperator: isOverloadedArithmeticOperator,
         receiverType: receiverType);
     inferrer.listener.methodInvocationExit(this, inferredType);
     return inferredType;
   }
 }
 
 /// Shadow object for [Not].
@@ skipping 844 matching lines @@
   }
 
   transformChildren(v) {
     return internalError("Internal error: Unsupported operation.");
   }
 
   visitChildren(v) {
     return internalError("Internal error: Unsupported operation.");
   }
 }