Use TypeChecker.fromUrl for all checkers

Eliminates usage of dart:mirrors

Author: kevmoo

json_serializable/lib/src/shared_checkers.dart

@@ -8,7 +8,7 @@ import 'package:source_gen/source_gen.dart' show TypeChecker;
 /// A [TypeChecker] for [Iterable].
 const coreIterableTypeChecker = TypeChecker.fromUrl('dart:core#Iterable');
 
-const coreStringTypeChecker = TypeChecker.fromRuntime(String);
+const coreStringTypeChecker = TypeChecker.fromUrl('dart:core#String');
 
 const coreMapTypeChecker = TypeChecker.fromUrl('dart:core#Map');
 
@@ -31,8 +31,8 @@ List<DartType> typeArgumentsOf(DartType type, TypeChecker checker) {
 /// A [TypeChecker] for [String], [bool] and [num].
 const simpleJsonTypeChecker = TypeChecker.any([
   coreStringTypeChecker,
-  TypeChecker.fromRuntime(bool),
-  TypeChecker.fromRuntime(num)
+  TypeChecker.fromUrl('dart:core#bool'),
+  TypeChecker.fromUrl('dart:core#num')
 ]);
 
 String asStatement(DartType type) {

json_serializable/lib/src/type_helpers/value_helper.dart

@@ -29,7 +29,7 @@ class ValueHelper extends TypeHelper {
     if (targetType.isDynamic || targetType.isObject) {
       // just return it as-is. We'll hope it's safe.
       return expression;
-    } else if (const TypeChecker.fromRuntime(double)
+    } else if (const TypeChecker.fromUrl('dart:core#double')
         .isExactlyType(targetType)) {
       return '($expression as num)${context.nullable ? '?' : ''}.toDouble()';
     } else if (simpleJsonTypeChecker.isAssignableFromType(targetType)) {