Add hook to register global object

pkg/dev_compiler/tool/input_sdk/private/js_helper.dart

Index: pkg/dev_compiler/tool/input_sdk/private/js_helper.dart
diff --git a/pkg/dev_compiler/tool/input_sdk/private/js_helper.dart b/pkg/dev_compiler/tool/input_sdk/private/js_helper.dart
index ccfce737c43f19d8250a2e4094fa9a6f5dea164c..ab0c443b6b333c323dd51fb1cf18eeefb80683f2 100644
--- a/pkg/dev_compiler/tool/input_sdk/private/js_helper.dart
+++ b/pkg/dev_compiler/tool/input_sdk/private/js_helper.dart
@@ -906,3 +906,6 @@ class SyncIterable<E> extends IterableBase<E> {
 class BooleanConversionAssertionError extends AssertionError {
   toString() => 'Failed assertion: boolean expression must not be null';
 }
+
+// Hook to register new global object.
+void registerGlobalObject(object) {}