Implement override-based type inference for instance methods.

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

Index: pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
index d3c0fd2b82ac09ce1b2ec329dac03770a3d2d39b..6e35f2bb3faab50a1be03b25d1b652ed71ef01cb 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_shadow_ast.dart
@@ -1317,6 +1317,9 @@ abstract class KernelMember implements Member {
     if (member._accessorNode != null) {
       member._accessorNode.overrides.add(overriddenMember);
     }
+    if (member is KernelProcedure && member._methodNode != null) {
+      member._methodNode.overrides.add(overriddenMember);
+    }
   }
 }
 
@@ -1475,10 +1478,15 @@ class KernelProcedure extends Procedure implements KernelMember {
   @override
   AccessorNode _accessorNode;
 
+  MethodNode _methodNode;
+
   @override
   KernelTypeInferrer _typeInferrer;
 
+  final bool _hasImplicitReturnType;
+
   KernelProcedure(Name name, ProcedureKind kind, FunctionNode function,
+      this._hasImplicitReturnType,
       {String fileUri})
       : super(name, kind, function, fileUri: fileUri);
 
@@ -1501,6 +1509,15 @@ class KernelProcedure extends Procedure implements KernelMember {
           'setInferredType called on a procedure that is not an accessor');
     }
   }
+
+  static MethodNode getMethodNode(Procedure procedure) {
+    if (procedure is KernelProcedure) return procedure._methodNode;
+    return null;
+  }
+
+  static bool hasImplicitReturnType(KernelProcedure procedure) {
+    return procedure._hasImplicitReturnType;
+  }
 }
 
 /// Concrete shadow object representing an assignment to a property.
@@ -1938,6 +1955,13 @@ class KernelTypeInferenceEngine extends TypeInferenceEngineImpl {
         this, uri.toString(), listener, false, thisType, null);
   }
 
+  @override
+  MethodNode createMethodNode(KernelProcedure procedure) {
+    MethodNode methodNode = new MethodNode(procedure);
+    procedure._methodNode = methodNode;
+    return methodNode;
+  }
+
   @override
   KernelTypeInferrer createTopLevelTypeInferrer(TypeInferenceListener listener,
       InterfaceType thisType, KernelMember member) {