Make the universe parts into small libraries.

pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart

Index: pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
diff --git a/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart b/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
index b10abf2aca6eac24e5d1e881138d6ab3ce8a2e49..a3ddc0a8f01b129103572bab8dc16a448568fc67 100644
--- a/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
+++ b/pkg/compiler/lib/src/js_emitter/program_builder/program_builder.dart
@@ -422,7 +422,7 @@ class ProgramBuilder {
     if (element == backend.closureClass) {
       // We add a special getter here to allow for tearing off a closure from
       // itself.
-      js.Name name = namer.getterForMember(Selector.CALL_NAME);
+      js.Name name = namer.getterForMember(Names.call);
       js.Fun function = js.js('function() { return this; }');
       callStubs.add(_buildStubMethod(name, function));
     }