Remove definitions from Kernel canonical names.

pkg/kernel/lib/ast.dart

Index: pkg/kernel/lib/ast.dart
diff --git a/pkg/kernel/lib/ast.dart b/pkg/kernel/lib/ast.dart
index 311d8c5051e34233c428ce1d4bb33292bf78a4eb..a27c198a9326d3d6d21fcbdd261217bed35c2d67 100644
--- a/pkg/kernel/lib/ast.dart
+++ b/pkg/kernel/lib/ast.dart
@@ -997,6 +997,7 @@ class Procedure extends Member {
   bool get isAccessor => isGetter || isSetter;
   bool get hasGetter => kind != ProcedureKind.Setter;
   bool get hasSetter => kind == ProcedureKind.Setter;
+  bool get isFactory => kind == ProcedureKind.Factory;
 
   accept(MemberVisitor v) => v.visitProcedure(this);