Lift nearly all top-level type inference restrictions.

pkg/front_end/lib/src/fasta/type_inference/type_inference_listener.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.md file.
 
+import 'package:front_end/src/fasta/type_inference/type_inference_engine.dart';
 import 'package:kernel/ast.dart';
 
 /// Base class for [TypeInferenceListener] that defines the API for debugging.
 ///
 /// By default no debug info is printed.  To enable debug printing, mix in
 /// [TypeInferenceDebugging].
 class TypeInferenceBase {
+  void debugDependency(FieldNode fieldNode) {}
+
   bool debugExpressionEnter(
       String expressionType, Expression expression, DartType typeContext) {
     return false;
   }
 
   void debugExpressionExit(
       String expressionType, Expression expression, DartType inferredType) {}
 
   void debugInitializerEnter(String initializerType, Initializer initializer) {}
 
   void debugInitializerExit(String initializerType, Initializer initializer) {}
 
   void debugStatementEnter(String statementType, Statement statement) {}
 
   void debugStatementExit(String statementType, Statement statement) {}
 }
 
 /// Mixin which can be applied to [TypeInferenceListener] to cause debug info to
 /// be printed.
 class TypeInferenceDebugging implements TypeInferenceBase {
+  void debugDependency(FieldNode fieldNode) {
+    print('Dependency $fieldNode');
+  }
+
   bool debugExpressionEnter(
       String expressionType, Expression expression, DartType typeContext) {
     print('Enter $expressionType($expression) (context=$typeContext)');
     return true;
   }
 
   void debugExpressionExit(
       String expressionType, Expression expression, DartType inferredType) {
     print('Exit $expressionType($expression) (type=$inferredType)');
   }
@@ skipping 75 matching lines @@
   void constructorInvocationExit(
           InvocationExpression expression, DartType inferredType) =>
       debugExpressionExit("constructorInvocation", expression, inferredType);
 
   bool doubleLiteralEnter(DoubleLiteral expression, DartType typeContext) =>
       debugExpressionEnter("doubleLiteral", expression, typeContext);
 
   void doubleLiteralExit(DoubleLiteral expression, DartType inferredType) =>
       debugExpressionExit("doubleLiteral", expression, inferredType);
 
+  void dryRunEnter(Expression expression) =>
+      debugExpressionEnter("dryRun", expression, null);
+
+  void dryRunExit(Expression expression) =>
+      debugExpressionExit("dryRun", expression, null);
+
   void expressionStatementEnter(ExpressionStatement statement) =>
       debugStatementEnter('expressionStatement', statement);
 
   void expressionStatementExit(ExpressionStatement statement) =>
       debugStatementExit('expressionStatement', statement);
 
   void forInStatementEnter(ForInStatement statement) =>
       debugStatementEnter('forInStatement', statement);
 
   void forInStatementExit(ForInStatement statement) =>
@@ skipping 86 matching lines @@
 
   void propertyGetExit(PropertyGet expression, DartType inferredType) =>
       debugExpressionExit("propertyGet", expression, inferredType);
 
   bool propertySetEnter(PropertySet expression, DartType typeContext) =>
       debugExpressionEnter("propertySet", expression, typeContext);
 
   void propertySetExit(PropertySet expression, DartType inferredType) =>
       debugExpressionExit("propertySet", expression, inferredType);
 
+  void recordDependency(FieldNode fieldNode) => debugDependency(fieldNode);
+
   void redirectingInitializerEnter(RedirectingInitializer initializer) =>
       debugInitializerEnter("redirectingInitializer", initializer);
 
   void redirectingInitializerExit(RedirectingInitializer initializer) =>
       debugInitializerExit("redirectingInitializer", initializer);
 
   void returnStatementEnter(ReturnStatement statement) =>
       debugStatementEnter('returnStatement', statement);
 
   void returnStatementExit(ReturnStatement statement) =>
@@ skipping 56 matching lines @@
 
   void variableSetExit(VariableSet expression, DartType inferredType) =>
       debugExpressionExit("variableSet", expression, inferredType);
 
   void yieldStatementEnter(YieldStatement statement) =>
       debugStatementEnter('yieldStatement', statement);
 
   void yieldStatementExit(YieldStatement statement) =>
       debugStatementExit('yieldStatement', statement);
 }