Send analysis notifications after subscription.

pkg/analyzer/lib/src/dart/analysis/driver.dart

Index: pkg/analyzer/lib/src/dart/analysis/driver.dart
diff --git a/pkg/analyzer/lib/src/dart/analysis/driver.dart b/pkg/analyzer/lib/src/dart/analysis/driver.dart
index b485d8557961b5eb4cbbfcb99d42f964737d2408..647e3992f89d2e29a922f81e5b58fe8a0b3dae93 100644
--- a/pkg/analyzer/lib/src/dart/analysis/driver.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/driver.dart
@@ -377,6 +377,14 @@ class AnalysisDriver {
   }
 
   /**
+   * Return `true` if the file with the given [path] was explicitly added
+   * to analysis using [addFile].
+   */
+  bool isAddedFile(String path) {
+    return _explicitFiles.contains(path);
+  }
+
+  /**
    * Returns a [Future] that completes after pumping the event queue [times]
    * times. By default, this should pump the event queue enough times to allow
    * any code to run, as long as it's not waiting on some external event.