Remove AstFactory from the front end.

pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart

Index: pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart
index 12a9d7a0afa48a060936ddd1540b92f623a98aab..bd4b8666fe83bc8d119798c7afcfed0b5e42a18f 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_library_builder.dart
@@ -593,8 +593,8 @@ class KernelLibraryBuilder
       List<Object> constantNamesAndOffsets, int charOffset, int charEndOffset) {
     addBuilder(
         name,
-        new KernelEnumBuilder(loader.astFactory, metadata, name,
-            constantNamesAndOffsets, this, charOffset, charEndOffset),
+        new KernelEnumBuilder(metadata, name, constantNamesAndOffsets, this,
+            charOffset, charEndOffset),
         charOffset);
   }