Fix couple problems with in-body incremental resolution.

pkg/analyzer/lib/src/context/cache.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.context.cache;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/file_system/file_system.dart';
@@ skipping 599 matching lines @@
    * Visit the given [result] and all results that depend on it, and
    * ask [delta] to gather changes. Return `true` if the [delta] can be used
    * to perform limited invalidation, or `false` if the changes collection
    * process does not stop (should not happen).
    */
   bool _gatherResultsInvalidatedByDelta(
       ResultDescriptor result, Delta delta, int level) {
     if (delta == null) {
       return false;
     }
+    if (!delta.gatherRequired()) {
+      return true;
+    }
     for (int i = 0; i < 64; i++) {
       bool hasVisitChanges = false;
       _visitResults(nextVisitId++, result,
           (AnalysisTarget target, ResultData data) {
         bool hasDeltaChanges = delta.gatherChanges(
             _partition.context, target, data.descriptor, data.value);
         if (hasDeltaChanges) {
           hasVisitChanges = true;
         }
       });
@@ skipping 618 matching lines @@
 }
 
 /**
  * The description for a change.
  */
 class Delta {
   final Source source;
 
   Delta(this.source);
 
+  /**
+   * This method is called during a cache walk, so that the delta can gather
+   * additional changes to which are caused by the changes it already knows
+   * about.  Return `true` if a new change was added, so that one more cache
+   * walk will be performed (to include changes that depend on results which we
+   * decided to be changed later in the previous cache walk).
+   */
   bool gatherChanges(InternalAnalysisContext context, AnalysisTarget target,
       ResultDescriptor descriptor, Object value) {
     return false;
   }
 
   /**
    * The current cache results visit is done.
    */
   void gatherEnd() {}
 
   /**
+   * Return `true` if this delta needs cache walking to gather additional
+   * changes before it can be used to [validate].  In this case [gatherChanges]
+   * is invoked for every targeted result in transitive dependencies, and
+   * [gatherEnd] is invoked after cache walking is done.
+   */
+  bool gatherRequired() {

[Brian Wilkerson, 2016/08/25 18:57:55]

This looks like it ought to be a getter.

+    return false;
+  }
+
+  /**
    * Check whether this delta affects the result described by the given
    * [descriptor] and [target]. The current [value] of the result is provided.
    */
   DeltaResult validate(InternalAnalysisContext context, AnalysisTarget target,
       ResultDescriptor descriptor, Object value) {
     return DeltaResult.INVALIDATE;
   }
 }
 
 /**
@@ skipping 229 matching lines @@
   void resultAccessed(TargetedResult result) {}
 
   @override
   List<TargetedResult> resultStored(TargetedResult newResult, newValue) {
     return TargetedResult.EMPTY_LIST;
   }
 
   @override
   void targetRemoved(AnalysisTarget target) {}
 }