Fix for PartDirective annotations while applying resynthesized element model.

pkg/analyzer/lib/src/generated/declaration_resolver.dart

Index: pkg/analyzer/lib/src/generated/declaration_resolver.dart
diff --git a/pkg/analyzer/lib/src/generated/declaration_resolver.dart b/pkg/analyzer/lib/src/generated/declaration_resolver.dart
index 86fcdb60cd05240aba831b0717f844b37f0dc47c..3fb363036a3613ec4c8c9c5f9538206a2ad7f208 100644
--- a/pkg/analyzer/lib/src/generated/declaration_resolver.dart
+++ b/pkg/analyzer/lib/src/generated/declaration_resolver.dart
@@ -339,8 +339,17 @@ class DeclarationResolver extends RecursiveAstVisitor<Object> {
   @override
   Object visitPartDirective(PartDirective node) {
     super.visitPartDirective(node);
-    _resolveAnnotations(
-        node, node.metadata, _enclosingUnit.getAnnotations(node.offset));
+    List<ElementAnnotation> annotations =
+        _enclosingUnit.getAnnotations(node.offset);
+    if (annotations.isEmpty && node.metadata.isNotEmpty) {
+      int index = (node.parent as CompilationUnit)
+          .directives
+          .where((directive) => directive is PartDirective)
+          .toList()
+          .indexOf(node);
+      annotations = _walker.element.library.parts[index].metadata;
+    }
+    _resolveAnnotations(node, node.metadata, annotations);
     return null;
   }