Fix for 'Extract Local' refactoring - take into account local variable elements.

pkg/analysis_server/test/services/refactoring/extract_local_test.dart

Index: pkg/analysis_server/test/services/refactoring/extract_local_test.dart
diff --git a/pkg/analysis_server/test/services/refactoring/extract_local_test.dart b/pkg/analysis_server/test/services/refactoring/extract_local_test.dart
index 6f657583c753b50bf5aa195d0a201653b9faa082..7ba11241c5118f578a9f2c1d7d3001579d41c1e2 100644
--- a/pkg/analysis_server/test/services/refactoring/extract_local_test.dart
+++ b/pkg/analysis_server/test/services/refactoring/extract_local_test.dart
@@ -596,6 +596,38 @@ main() {
 ''');
   }
 
+  test_occurences_differentVariable() {
+    indexTestUnit('''
+main() {
+  {
+    int v = 1;
+    print(v + 1); // marker
+    print(v + 1);
+  }
+  {
+    int v = 2;
+    print(v + 1);
+  }
+}
+''');
+    _createRefactoringWithSuffix('v + 1', '); // marker');
+    // apply refactoring
+    return _assertSuccessfulRefactoring('''
+main() {
+  {
+    int v = 1;
+    var res = v + 1;
+    print(res); // marker
+    print(res);
+  }
+  {
+    int v = 2;
+    print(v + 1);
+  }
+}
+''');
+  }
+
   test_occurences_useDominator() {
     indexTestUnit('''
 main() {