enable compatiblity with 1.18 SDKs

fixes #584, works around analyzer message #583

R=leafp@google.com

Review URL: https://codereview.chromium.org/2048463002 .

lib/src/compiler/code_generator.dart

@@ -11,10 +11,9 @@ import 'package:analyzer/dart/ast/token.dart' show Token, TokenType;
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/dart/ast/token.dart' show StringToken;
-//TODO(leafp): Remove deprecated dependency
-//ignore: DEPRECATED_MEMBER_USE
-import 'package:analyzer/src/generated/element.dart'
-    show DynamicTypeImpl, LocalVariableElementImpl;
+import 'package:analyzer/src/dart/element/element.dart'
+    show LocalVariableElementImpl;
+import 'package:analyzer/src/dart/element/type.dart' show DynamicTypeImpl;
 import 'package:analyzer/src/generated/engine.dart' show AnalysisContext;
 import 'package:analyzer/src/generated/resolver.dart'
     show TypeProvider, NamespaceBuilder;
@@ -291,6 +290,7 @@ class CodeGenerator extends GeneralizingAstVisitor
       case ModuleFormat.es6:
         return module;
     }
+    return null; // unreachable. It is here to suppress a bogus Analyzer message
   }
 
   List<String> _getJSName(Element e) {
@@ -2169,7 +2169,6 @@ class CodeGenerator extends GeneralizingAstVisitor
     } else {
       return js.call('dart.fn(#, #)', [fn, typeRep]);
     }
-    throw 'Function has non function type: $type';
   }
 
   /// Emits an arrow FunctionExpression node.

pubspec.lock

@@ -289,4 +289,4 @@ packages:
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.1.9"
-sdk: ">=1.16.0 <1.18.0"
+sdk: ">=1.16.0 <2.0.0"

pubspec.yaml

@@ -29,6 +29,10 @@ dev_dependencies:
   unittest: ^0.11.6
   webdriver: ^0.8.8
 
+dependency_overrides:
+  # Remove once there is a package:test that allows 1.18 SDKs in its contraint.
+  test: ^0.12.0
+
 environment:
   sdk: ">=1.12.0 <2.0.0"