If there is a changed file, hasFilesToAnalyze is true.

pkg/analyzer/test/src/dart/analysis/driver_test.dart

Index: pkg/analyzer/test/src/dart/analysis/driver_test.dart
diff --git a/pkg/analyzer/test/src/dart/analysis/driver_test.dart b/pkg/analyzer/test/src/dart/analysis/driver_test.dart
index 65c4f8e21530cce244fff8132eb2a24a667c3fc8..46c17437c5cb6c8d1d6fd2d5c7b8b65e43f75e60 100644
--- a/pkg/analyzer/test/src/dart/analysis/driver_test.dart
+++ b/pkg/analyzer/test/src/dart/analysis/driver_test.dart
@@ -998,6 +998,12 @@ main() {
     await future;
     expect(driver.hasFilesToAnalyze, isFalse);
 
+    // Change a file, even if not added, it still might affect analysis.
+    driver.changeFile(_p('/not/added.dart'));
+    expect(driver.hasFilesToAnalyze, isTrue);
+    await _waitForIdle();
+    expect(driver.hasFilesToAnalyze, isFalse);
+
     // Request of referenced names is not analysis of a file.
     driver.getFilesReferencingName('X');
     expect(driver.hasFilesToAnalyze, isFalse);