Fix some issues with options handling

pkg/analyzer/lib/src/context/builder.dart

Index: pkg/analyzer/lib/src/context/builder.dart
diff --git a/pkg/analyzer/lib/src/context/builder.dart b/pkg/analyzer/lib/src/context/builder.dart
index 899e738cf1e0ba18843182b2fae43b7591db2628..5c70a2bf5f536527f82f71611add2a24a3c90c6b 100644
--- a/pkg/analyzer/lib/src/context/builder.dart
+++ b/pkg/analyzer/lib/src/context/builder.dart
@@ -817,7 +817,10 @@ class _BasicWorkspace extends Workspace {
       throw new ArgumentError('not absolute: $path');
     }
     path = context.normalize(path);
-
+    Resource resource = provider.getResource(path);
+    if (resource is File) {
+      path = resource.parent.path;
+    }
     return new _BasicWorkspace._(provider, path, builder);
   }
 }