Migrate DDC to the new analysis driver.

pkg/analyzer/lib/src/summary/package_bundle_reader.dart

Index: pkg/analyzer/lib/src/summary/package_bundle_reader.dart
diff --git a/pkg/analyzer/lib/src/summary/package_bundle_reader.dart b/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
index bf9361d635a98998ae98d5043308a59502c61d3e..a8711e6231881ef35d5f8ee0d502399c7c0eb8b3 100644
--- a/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
+++ b/pkg/analyzer/lib/src/summary/package_bundle_reader.dart
@@ -412,7 +412,6 @@ class SummaryDataStore {
    * the given [unitUriString], or `null` if no such library is in the store.
    */
   List<String> getContainingLibraryUris(String unitUriString) {
-
     // The unit is the defining unit of a library.
     if (linkedMap.containsKey(unitUriString)) {
       return <String>[unitUriString];
@@ -433,6 +432,14 @@ class SummaryDataStore {
     return libraryUriStrings.isNotEmpty ? libraryUriStrings : null;
   }
 
+  /**
+   * Return `true` if the store contains the unlinked summary for the unit
+   * with the given absolute [uri].
+   */
+  bool hasUnlinkedUnit(String uri) {
+    return unlinkedMap.containsKey(uri);
+  }
+
   void _fillMaps(String path, ResourceProvider resourceProvider) {
     List<int> buffer;
     if (resourceProvider != null) {
@@ -445,4 +452,12 @@ class SummaryDataStore {
     PackageBundle bundle = new PackageBundle.fromBuffer(buffer);
     addBundle(path, bundle);
   }
+
+  /**
+   * TODO(scheglov) document
+   */
+  void addStore(SummaryDataStore other) {
+    unlinkedMap.addAll(other.unlinkedMap);
+    linkedMap.addAll(other.linkedMap);
+  }
 }