DDC fixes on DDC

This isn't everything by far, but most issues local to DDC itself that
we mark error right now.  There are a bunch of down casts around
literals and not-quite-generic methods.

[email protected]

Review URL: https://codereview.chromium.org/963063003

Author: vsmenon

lib/config.dart

@@ -8,7 +8,7 @@ library ddc.config;
 // Options shared by the compiler and runtime.
 class TypeOptions {
   static const NONNULLABLE_TYPES = const <String>['int', 'double'];
-  final nonnullableTypes;
+  final List<String> nonnullableTypes;
 
   TypeOptions({this.nonnullableTypes: NONNULLABLE_TYPES});
 }

lib/src/codegen/js_codegen.dart

@@ -315,7 +315,7 @@ class JSCodegenVisitor extends GeneralizingAstVisitor with ConversionVisitor {
     // If we don't have a method body, skip this.
     if (fields.isEmpty) return null;
 
-    var body = _initializeFields(fields);
+    dynamic body = _initializeFields(fields);
     var superCall = _superConstructorCall(node);
     if (superCall != null) body = [[body, superCall]];
     return new JS.Method(

lib/src/js/printer.dart

@@ -1285,7 +1285,7 @@ class DanglingElseVisitor extends BaseVisitor<bool> {
 
   bool visitProgram(Program node) => false;
 
-  bool visitNode(Statement node) {
+  bool visitNode(Node node) {
     context.error("Forgot node: $node");
     return null;
   }

lib/src/js/template.dart

@@ -125,7 +125,7 @@ class Template {
  * trees. [arguments] is a List for positional templates, or Map for
  * named templates.
  */
-typedef Node Instantiator(var arguments);
+typedef Instantiator(var arguments);
 
 
 /**

lib/src/options.dart

@@ -54,7 +54,7 @@ class ResolverOptions {
   final bool onlyInferConstsAndFinalFields;
 
   ResolverOptions({this.useMultiPackage: false, this.packageRoot: 'packages/',
-      this.packagePaths: const [], this.inferFromOverrides: true,
+      this.packagePaths: const <String>[], this.inferFromOverrides: true,
       this.inferStaticsFromIdentifiers: false,
       this.inferInNonStableOrder: false,
       this.onlyInferConstsAndFinalFields: false});
@@ -187,7 +187,7 @@ class CompilerOptions implements RulesOptions, ResolverOptions {
       this.outputDart: false, this.useColors: true,
       this.covariantGenerics: true, this.relaxedCasts: true,
       this.useMultiPackage: false, this.packageRoot: 'packages/',
-      this.packagePaths: const [], this.inferFromOverrides: true,
+      this.packagePaths: const <String>[], this.inferFromOverrides: true,
       this.inferStaticsFromIdentifiers: false,
       this.inferInNonStableOrder: false,
       this.onlyInferConstsAndFinalFields: false,