Fix for invalidating results of a target being removed.

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

Index: pkg/analyzer/lib/src/context/context.dart
diff --git a/pkg/analyzer/lib/src/context/context.dart b/pkg/analyzer/lib/src/context/context.dart
index 03f69d44f4fa411ea9a48d31ca8aad44b4d67d70..c0f60ffa5f560a46e06dac4322dbe1a5e565e193 100644
--- a/pkg/analyzer/lib/src/context/context.dart
+++ b/pkg/analyzer/lib/src/context/context.dart
@@ -1656,8 +1656,8 @@ class AnalysisContextImpl implements InternalAnalysisContext {
     if (entry == null) {
       _createCacheEntry(source, true);
     } else {
-      // TODO(brianwilkerson) Implement this.
-//      _propagateInvalidation(source, entry);
+      entry.modificationTime = getModificationStamp(source);
+      entry.setState(CONTENT, CacheState.INVALID);
     }
   }
 
@@ -1688,8 +1688,7 @@ class AnalysisContextImpl implements InternalAnalysisContext {
       } catch (e) {}
     }
     // We need to invalidate the cache.
-    // TODO(brianwilkerson) Implement this.
-//    _propagateInvalidation(source, entry);
+    entry.setState(CONTENT, CacheState.INVALID);
   }
 
   /**