Refactor strong mode to use standard Analyzer errors

pkg/analyzer/lib/src/task/strong/ast_properties.dart

+// Copyright (c) 2016, 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.
+
+/// Properties that result from Strong Mode analysis on an AST.
+///
+/// These properties are not public, but provided by use of back-ends such as
+/// Dart Dev Compiler.
+
+import 'package:analyzer/analyzer.dart';
+import 'package:analyzer/dart/element/type.dart';
+
+const String _implicitCast = '_implicitCast';
+const String _hasImplicitCasts = '_hasImplicitCasts';
+const String _isDynamicInvoke = '_isDynamicInvoke';
+
+/// True if this compilation unit has any implicit casts, otherwise false.
+///
+/// See also [getImplicitCast].
+bool hasImplicitCasts(CompilationUnit node) {

[Jennifer Messerly, 2016/06/10 22:59:24]

testing out the DDC side, I realized this short-circuit feature was
unimplemented. :)

I can either rip it out or fix it. Currently working towards the latter.

[Jennifer Messerly, 2016/06/10 23:13:12]

FYI -- DDC side is passing now. That CL is here:
https://codereview.chromium.org/2057373003

+  return node.getProperty/*<bool>*/(_hasImplicitCasts) ?? false;
+}
+
+/// Sets [hasImplicitCasts] property for this compilation unit.
+void setHasImplicitCasts(CompilationUnit node, bool value) {
+  node.setProperty(_hasImplicitCasts, value == true ? true : null);
+}
+
+/// If this expression has an implicit cast, returns the type it is coerced to,
+/// otherwise returns null.
+DartType getImplicitCast(Expression node) {
+  return node.getProperty/*<DartType>*/(_implicitCast);
+}
+
+/// Sets the result of [getImplicitCast] for this node.
+void setImplicitCast(Expression node, DartType type) {
+  node.setProperty(_implicitCast, type);
+}
+
+/// True if this node is a dynamic operation that requires dispatch and/or
+/// checking at runtime.
+bool isDynamicInvoke(Expression node) {
+  return node.getProperty/*<bool>*/(_isDynamicInvoke) ?? false;
+}
+
+/// Sets [isDynamicInvoke] property for this expression
+void setIsDynamicInvoke(Expression node, bool value) {
+  node.setProperty(_isDynamicInvoke, value == true ? true : null);
+}