Reapply "Add "load from .dill" file capability and run a white-box test.""

pkg/compiler/lib/src/kernel/kernel.dart

Index: pkg/compiler/lib/src/kernel/kernel.dart
diff --git a/pkg/compiler/lib/src/kernel/kernel.dart b/pkg/compiler/lib/src/kernel/kernel.dart
index 7bd80043c71267fc570896e6c95368a6e81a7a65..f8bf39f66179f83d8590563775e31b6b393c5863 100644
--- a/pkg/compiler/lib/src/kernel/kernel.dart
+++ b/pkg/compiler/lib/src/kernel/kernel.dart
@@ -35,6 +35,7 @@ import '../elements/elements.dart'
         MetadataAnnotation,
         MixinApplicationElement,
         TypeVariableElement;
+import '../elements/entities.dart' show LibraryEntity;
 import '../elements/modelx.dart' show ErroneousFieldElementX;
 import '../tree/tree.dart' show FunctionExpression, Node;
 import 'constant_visitor.dart';
@@ -609,7 +610,7 @@ class Kernel {
     throw message;
   }
 
-  forEachLibraryElement(f(LibraryElement library)) {
+  forEachLibraryElement(f(LibraryEntity library)) {
     return compiler.libraryLoader.libraries.forEach(f);
   }