fix for 1.12.0-dev SDK and 0.25.1 analyzer breaking changes

lib/src/codegen/reify_coercions.dart

Index: lib/src/codegen/reify_coercions.dart
diff --git a/lib/src/codegen/reify_coercions.dart b/lib/src/codegen/reify_coercions.dart
index ddda6f7224479dc23c485be7a453289f4d3a4518..feafc51a5140af524d50eca491efb9ef4275cb2d 100644
--- a/lib/src/codegen/reify_coercions.dart
+++ b/lib/src/codegen/reify_coercions.dart
@@ -430,7 +430,7 @@ class TypeManager {
     // This is the type corresponding to the typedef.  Note that
     // almost all methods on this type delegate to the element, so it
     // cannot be safely be used for anything until the element is fully resolved
-    FunctionTypeImpl substType = new FunctionTypeImpl.con2(element);
+    FunctionTypeImpl substType = new FunctionTypeImpl.forTypedef(element);
     element.type = substType;
     // Link the type and the element into the identifier for the typedef
     t.staticType = substType;