Initial support for an explicit plugin list

pkg/analyzer/test/generated/engine_test.dart

Index: pkg/analyzer/test/generated/engine_test.dart
diff --git a/pkg/analyzer/test/generated/engine_test.dart b/pkg/analyzer/test/generated/engine_test.dart
index 7606c653dbaf19c3b8e94d4b1ea71064e26c3330..12c4b4e8402ae9ebddf1184b37d186353b120eec 100644
--- a/pkg/analyzer/test/generated/engine_test.dart
+++ b/pkg/analyzer/test/generated/engine_test.dart
@@ -40,6 +40,7 @@ class AnalysisOptionsImplTest {
     AnalysisOptionsImpl modifiedOptions = new AnalysisOptionsImpl();
     modifiedOptions.dart2jsHint = true;
     modifiedOptions.disableCacheFlushing = true;
+    modifiedOptions.enabledPluginNames = ['somePackage'];
     modifiedOptions.enableAssertInitializer = true;
     modifiedOptions.enableLazyAssignmentOperators = true;
     modifiedOptions.enableStrictCallChecks = true;
@@ -65,6 +66,7 @@ class AnalysisOptionsImplTest {
     expect(modifiedOptions.dart2jsHint, defaultOptions.dart2jsHint);
     expect(modifiedOptions.disableCacheFlushing,
         defaultOptions.disableCacheFlushing);
+    expect(modifiedOptions.enabledPluginNames, isEmpty);
     expect(modifiedOptions.enableAssertInitializer,
         defaultOptions.enableAssertInitializer);
     expect(modifiedOptions.enableLazyAssignmentOperators,