Prepare for chaining resynthesizers from AC to SDK AC.

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

Index: pkg/analyzer/lib/src/summary/summary_sdk.dart
diff --git a/pkg/analyzer/lib/src/summary/summary_sdk.dart b/pkg/analyzer/lib/src/summary/summary_sdk.dart
index 4d9b9feb6ce4ce6b59fabe8221debbe1dcc68723..2a7e10b7c66bb0c07b7a456e67d49be9abd81732 100644
--- a/pkg/analyzer/lib/src/summary/summary_sdk.dart
+++ b/pkg/analyzer/lib/src/summary/summary_sdk.dart
@@ -10,8 +10,10 @@ import 'package:analyzer/src/context/cache.dart' show CacheEntry;
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/dart/element/type.dart';
 import 'package:analyzer/src/generated/constant.dart';
+import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/resolver.dart';
-import 'package:analyzer/src/generated/source.dart' show Source, SourceKind;
+import 'package:analyzer/src/generated/source.dart'
+    show DartUriResolver, Source, SourceFactory, SourceKind;
 import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/resynthesize.dart';
 import 'package:analyzer/src/task/dart.dart'
@@ -32,32 +34,30 @@ import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/model.dart'
     show AnalysisTarget, ResultDescriptor, TargetedResult;
 
-/**
- * An [SdkAnalysisContext] for Dart SDK with a summary [SdkBundle].
- */
-class SummarySdkAnalysisContext extends SdkAnalysisContext {
+class SdkSummaryResultProvider extends AboutToComputeResultHelper {
   final SdkBundle bundle;
   final SummaryTypeProvider typeProvider = new SummaryTypeProvider();
-
-  SummaryResynthesizer resynthesizer;
-
-  SummarySdkAnalysisContext(this.bundle);
+  SummaryResynthesizer summaryResynthesizer;
+
+  SdkSummaryResultProvider(InternalAnalysisContext context, this.bundle)
+      : super(context) {
+    summaryResynthesizer = new SummaryResynthesizer(context, typeProvider,
+        _getPrelinkedSummary, _getUnlinkedSummary, context.sourceFactory);
+    _buildCoreLibrary();
+    _buildAsyncLibrary();
+    summaryResynthesizer.finalizeCoreAsyncLibraries();
+  }
 
   @override
-  bool aboutToComputeResult(CacheEntry entry, ResultDescriptor result) {
-    if (resynthesizer == null) {
-      resynthesizer = new SummaryResynthesizer(this, typeProvider,
-          _getPrelinkedSummary, _getUnlinkedSummary, sourceFactory);
-      _buildCoreLibrary();
-      _buildAsyncLibrary();
-    }
+  bool compute(CacheEntry entry, ResultDescriptor result) {
     if (result == TYPE_PROVIDER) {
+//      print('SummarySdkAnalysisContext: $result');
       entry.setValue(result, typeProvider, TargetedResult.EMPTY_LIST);
       return true;
     }
     AnalysisTarget target = entry.target;
-//    print('SummarySdkAnalysisContext: $result of $target');
     if (target is Source && target.isInSystemLibrary) {
+//      print('SummarySdkAnalysisContext: $result of $target');
       if (result == LIBRARY_ELEMENT1 ||
           result == LIBRARY_ELEMENT2 ||
           result == LIBRARY_ELEMENT3 ||
@@ -70,7 +70,8 @@ class SummarySdkAnalysisContext extends SdkAnalysisContext {
         // TODO(scheglov) try to find a way to avoid listing every result
         // e.g. "result.whenComplete == LIBRARY_ELEMENT"
         String uri = target.uri.toString();
-        LibraryElement libraryElement = resynthesizer.getLibraryElement(uri);
+        LibraryElement libraryElement =
+            summaryResynthesizer.getLibraryElement(uri);
         entry.setValue(result, libraryElement, TargetedResult.EMPTY_LIST);
         return true;
       } else if (result == READY_LIBRARY_ELEMENT2 ||
@@ -80,12 +81,9 @@ class SummarySdkAnalysisContext extends SdkAnalysisContext {
         return true;
       } else if (result == SOURCE_KIND) {
         String uri = target.uri.toString();
-        if (bundle.prelinkedLibraryUris.contains(uri)) {
-          entry.setValue(result, SourceKind.LIBRARY, TargetedResult.EMPTY_LIST);
-          return true;
-        }
-        if (bundle.unlinkedUnitUris.contains(uri)) {
-          entry.setValue(result, SourceKind.PART, TargetedResult.EMPTY_LIST);
+        SourceKind kind = _getSourceKind(uri);
+        if (kind != null) {
+          entry.setValue(result, kind, TargetedResult.EMPTY_LIST);
           return true;
         }
         return false;
@@ -97,15 +95,20 @@ class SummarySdkAnalysisContext extends SdkAnalysisContext {
   }
 
   void _buildAsyncLibrary() {
-    LibraryElement library = resynthesizer.getLibraryElement('dart:async');
+    LibraryElement library =
+        summaryResynthesizer.getLibraryElement('dart:async');
     typeProvider.initializeAsync(library);
   }
 
   void _buildCoreLibrary() {
-    LibraryElement library = resynthesizer.getLibraryElement('dart:core');
+    LibraryElement library =
+        summaryResynthesizer.getLibraryElement('dart:core');
     typeProvider.initializeCore(library);
   }
 
+  /**
+   * Return the [PrelinkedLibrary] for the given [uri] or throw [StateError].
+   */
   PrelinkedLibrary _getPrelinkedSummary(String uri) {
     for (int i = 0; i < bundle.prelinkedLibraryUris.length; i++) {
       if (bundle.prelinkedLibraryUris[i] == uri) {
@@ -115,6 +118,22 @@ class SummarySdkAnalysisContext extends SdkAnalysisContext {
     throw new StateError('Unable to find prelinked summary for $uri');
   }
 
+  /**
+   * Return the [SourceKind] of the given [uri] or `null` if it is unknown.
+   */
+  SourceKind _getSourceKind(String uri) {
+    if (bundle.prelinkedLibraryUris.contains(uri)) {
+      return SourceKind.LIBRARY;
+    }
+    if (bundle.unlinkedUnitUris.contains(uri)) {
+      return SourceKind.PART;
+    }
+    return null;
+  }
+
+  /**
+   * Return the [UnlinkedUnit] for the given [uri] or throw [StateError].
+   */
   UnlinkedUnit _getUnlinkedSummary(String uri) {
     for (int i = 0; i < bundle.unlinkedUnitUris.length; i++) {
       if (bundle.unlinkedUnitUris[i] == uri) {