Fix ResynthesizerResultProvider's handling of parts.

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

 import 'dart:io' as io;
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_io.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
@@ skipping 122 matching lines @@
     _dataStore.addBundle(path, bundle);
   }
 
   @override
   bool compute(CacheEntry entry, ResultDescriptor result) {
     if (_sdkProvider != null && _sdkProvider.compute(entry, result)) {
       return true;
     }
     AnalysisTarget target = entry.target;
     // Check whether there are results for the source.
-    if (!hasResultsForSource(target.source)) {
+    if (!hasResultsForSource(target.librarySource ?? target.source)) {
       return false;
     }
     // Constant expressions are always resolved in summaries.
     if (result == CONSTANT_EXPRESSION_RESOLVED &&
         target is ConstantEvaluationTarget) {
       entry.setValue(result, true, TargetedResult.EMPTY_LIST);
       return true;
     }
     // Provide results for Source.
     if (target is Source) {
@@ skipping 23 matching lines @@
           entry.setValue(result, SourceKind.LIBRARY, TargetedResult.EMPTY_LIST);
           return true;
         }
         if (_dataStore.unlinkedMap.containsKey(uriString)) {
           entry.setValue(result, SourceKind.PART, TargetedResult.EMPTY_LIST);
           return true;
         }
         return false;
       }
     } else if (target is LibrarySpecificUnit) {
-      if (!hasResultsForSource(target.library)) {
-        return false;
-      }
       if (result == CREATED_RESOLVED_UNIT1 ||
           result == CREATED_RESOLVED_UNIT2 ||
           result == CREATED_RESOLVED_UNIT3 ||
           result == CREATED_RESOLVED_UNIT4 ||
           result == CREATED_RESOLVED_UNIT5 ||
           result == CREATED_RESOLVED_UNIT6 ||
           result == CREATED_RESOLVED_UNIT7 ||
           result == CREATED_RESOLVED_UNIT8 ||
           result == CREATED_RESOLVED_UNIT9 ||
           result == CREATED_RESOLVED_UNIT10 ||
           result == CREATED_RESOLVED_UNIT11 ||
           result == CREATED_RESOLVED_UNIT12) {
         entry.setValue(result, true, TargetedResult.EMPTY_LIST);
         return true;
       }
       if (result == COMPILATION_UNIT_ELEMENT) {
         String libraryUri = target.library.uri.toString();
         String unitUri = target.unit.uri.toString();
         CompilationUnitElement unit = resynthesizer.getElement(
             new ElementLocationImpl.con3(<String>[libraryUri, unitUri]));
         if (unit != null) {
           entry.setValue(result, unit, TargetedResult.EMPTY_LIST);
           return true;
         }
       }
     } else if (target is VariableElement) {
-      if (!hasResultsForSource(target.library.source)) {
-        return false;
-      }
       if (result == PROPAGATED_VARIABLE || result == INFERRED_STATIC_VARIABLE) {
         entry.setValue(result, target, TargetedResult.EMPTY_LIST);
         return true;
       }
     }
     // Unknown target.
     return false;
   }
 
   /**
@@ skipping 117 matching lines @@
  * also provides [summaryPath].
  */
 class _InSummaryFallbackSource extends FileBasedSource
     implements InSummarySource {
   @override
   final String summaryPath;
 
   _InSummaryFallbackSource(JavaFile file, Uri uri, this.summaryPath)
       : super(file, uri);
 }