Prepare for development branch by updating externally-used API.

pkg/analyzer/test/generated/parser_fasta_test.dart

Index: pkg/analyzer/test/generated/parser_fasta_test.dart
diff --git a/pkg/analyzer/test/generated/parser_fasta_test.dart b/pkg/analyzer/test/generated/parser_fasta_test.dart
index 32364691a45c9a8d5c7f47ae69d235f8a984afb2..18605a439237f37987b440b3fe3010fc5b3c56e4 100644
--- a/pkg/analyzer/test/generated/parser_fasta_test.dart
+++ b/pkg/analyzer/test/generated/parser_fasta_test.dart
@@ -830,8 +830,9 @@ class ScopeProxy implements Scope {
   final _locals = <String, Builder>{};
 
   @override
-  void operator []=(String name, Builder member) {
-    _locals[name] = member;
+  declare(String name, Builder builder, int charOffset, Uri fileUri) {
+    _locals[name] = builder;
+    return null;
   }
 
   @override