diff --git a/pkg/analyzer/lib/src/dart/analysis/library_context.dart b/pkg/analyzer/lib/src/dart/analysis/library_context.dart
index 5b85508..9c82bd8 100644
--- a/pkg/analyzer/lib/src/dart/analysis/library_context.dart
+++ b/pkg/analyzer/lib/src/dart/analysis/library_context.dart
@@ -173,7 +173,7 @@
       }, (String uri) {
         UnlinkedUnit unlinkedUnit = store.unlinkedMap[uri];
         return unlinkedUnit;
-      }, (_) => null, analysisContext.analysisOptions);
+      }, DeclaredVariables(), analysisContext.analysisOptions);
       logger.writeln('Linked ${linkedLibraries.length} libraries.');
     });
 
diff --git a/pkg/analyzer/lib/src/summary/link.dart b/pkg/analyzer/lib/src/summary/link.dart
index c7e24ab..d38b602 100644
--- a/pkg/analyzer/lib/src/summary/link.dart
+++ b/pkg/analyzer/lib/src/summary/link.dart
@@ -55,6 +55,7 @@
 ///
 /// - Where possible, we favor method dispatch instead of "is" and "as"
 ///   checks.  E.g. see [ReferenceableElementForLink.asConstructor].
+import 'package:analyzer/dart/analysis/declared_variables.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/standard_ast_factory.dart';
@@ -114,11 +115,11 @@
     Set<String> libraryUris,
     GetDependencyCallback getDependency,
     GetUnitCallback getUnit,
-    GetDeclaredVariable getDeclaredVariable,
+    DeclaredVariables declaredVariables,
     AnalysisOptions analysisOptions,
     [GetAstCallback getAst]) {
   Map<String, LinkedLibraryBuilder> linkedLibraries =
-      setupForLink(libraryUris, getUnit, getDeclaredVariable);
+      setupForLink(libraryUris, getUnit, declaredVariables);
   _relink(linkedLibraries, getDependency, getUnit, getAst, analysisOptions);
   return linkedLibraries;
 }
@@ -131,7 +132,7 @@
 /// of the libraries in this build unit, and whose values are the corresponding
 /// [LinkedLibraryBuilder]s.
 Map<String, LinkedLibraryBuilder> setupForLink(Set<String> libraryUris,
-    GetUnitCallback getUnit, GetDeclaredVariable getDeclaredVariable) {
+    GetUnitCallback getUnit, DeclaredVariables declaredVariables) {
   Map<String, LinkedLibraryBuilder> linkedLibraries =
       <String, LinkedLibraryBuilder>{};
   for (String absoluteUri in libraryUris) {
@@ -140,7 +141,7 @@
         getUnit(absoluteUri),
         getUnit,
         (String absoluteUri) => getUnit(absoluteUri)?.publicNamespace,
-        getDeclaredVariable);
+        declaredVariables);
   }
   return linkedLibraries;
 }
diff --git a/pkg/analyzer/lib/src/summary/prelink.dart b/pkg/analyzer/lib/src/summary/prelink.dart
index 6bda8fd..1785442 100644
--- a/pkg/analyzer/lib/src/summary/prelink.dart
+++ b/pkg/analyzer/lib/src/summary/prelink.dart
@@ -2,6 +2,7 @@
 // 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.
 
+import 'package:analyzer/dart/analysis/declared_variables.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/idl.dart';
@@ -21,19 +22,13 @@
     UnlinkedUnit definingUnit,
     GetPartCallback getPart,
     GetImportCallback getImport,
-    GetDeclaredVariable getDeclaredVariable) {
-  return new _Prelinker(definingUnitUri, definingUnit, getPart, getImport,
-          getDeclaredVariable)
+    DeclaredVariables declaredVariables) {
+  return new _Prelinker(
+          definingUnitUri, definingUnit, getPart, getImport, declaredVariables)
       .prelink();
 }
 
 /**
- * Return the raw string value of the variable with the given [name],
- * or `null` of the variable is not defined.
- */
-typedef String GetDeclaredVariable(String name);
-
-/**
  * Type of the callback used by the prelinker to obtain public namespace
  * information about libraries with the given [absoluteUri] imported by the
  * library to be prelinked (and the transitive closure of parts and exports
@@ -219,7 +214,7 @@
   final UnlinkedUnit definingUnit;
   final GetPartCallback getPart;
   final GetImportCallback getImport;
-  final GetDeclaredVariable getDeclaredVariable;
+  final DeclaredVariables declaredVariables;
 
   /**
    * Cache of values returned by [getImport].
@@ -263,7 +258,7 @@
   final Map<String, _ExportNamespace> exportNamespaces = {};
 
   _Prelinker(this.definingUnitUri, this.definingUnit, this.getPart,
-      this.getImport, this.getDeclaredVariable) {
+      this.getImport, this.declaredVariables) {
     partCache[definingUnitUri] = definingUnit;
     importCache[definingUnitUri] = definingUnit.publicNamespace;
   }
@@ -719,7 +714,7 @@
   String _selectUri(
       String defaultUri, List<UnlinkedConfiguration> configurations) {
     for (UnlinkedConfiguration configuration in configurations) {
-      if (getDeclaredVariable(configuration.name) == configuration.value) {
+      if (declaredVariables.get(configuration.name) == configuration.value) {
         return configuration.uri;
       }
     }
diff --git a/pkg/analyzer/lib/src/summary/summary_file_builder.dart b/pkg/analyzer/lib/src/summary/summary_file_builder.dart
index 5f2a56b..f774d2a 100644
--- a/pkg/analyzer/lib/src/summary/summary_file_builder.dart
+++ b/pkg/analyzer/lib/src/summary/summary_file_builder.dart
@@ -4,6 +4,7 @@
 
 import 'dart:collection';
 
+import 'package:analyzer/dart/analysis/declared_variables.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/error/listener.dart';
@@ -90,9 +91,7 @@
         throw new StateError('Unable to find unresolved unit $uri.');
       }
       return unlinked;
-    }, (String name) {
-      throw new StateError('Unexpected call to GetDeclaredVariable($name).');
-    }, context.analysisOptions);
+    }, DeclaredVariables(), context.analysisOptions);
     map.forEach(bundleAssembler.addLinkedLibrary);
 
     return bundleAssembler.assemble().toBuffer();
diff --git a/pkg/analyzer/test/src/summary/test_strategies.dart b/pkg/analyzer/test/src/summary/test_strategies.dart
index 0d08da6..bfbe9fe 100644
--- a/pkg/analyzer/test/src/summary/test_strategies.dart
+++ b/pkg/analyzer/test/src/summary/test_strategies.dart
@@ -176,7 +176,7 @@
         .toSet();
 
     Map<String, LinkedLibrary> linkedSummaries = link(nonSdkLibraryUris,
-        getDependency, getUnit, declaredVariables.get, analysisOptions);
+        getDependency, getUnit, declaredVariables, analysisOptions);
 
     var analysisContext = RestrictedAnalysisContext(
       analysisOptions,
@@ -250,7 +250,7 @@
     UnlinkedUnit definingUnit = _getUnlinkedUnit(librarySource);
     if (definingUnit != null) {
       LinkedLibraryBuilder linkedLibrary = prelink(librarySource.uri.toString(),
-          definingUnit, getPart, getImport, declaredVariables.get);
+          definingUnit, getPart, getImport, declaredVariables);
       linkedLibrary.dependencies.skip(1).forEach((LinkedDependency d) {
         Source source = sourceFactory.forUri(d.uri);
         _serializeLibrary(source);
@@ -377,11 +377,12 @@
     }
 
     linked = new LinkedLibrary.fromBuffer(prelink(
-        _linkerInputs._testDartUri.toString(),
-        _linkerInputs._unlinkedDefiningUnit,
-        getPart,
-        getImport,
-        (String declaredVariable) => null).toBuffer());
+            _linkerInputs._testDartUri.toString(),
+            _linkerInputs._unlinkedDefiningUnit,
+            getPart,
+            getImport,
+            DeclaredVariables())
+        .toBuffer());
     _validateLinkedLibrary(linked);
   }
 }
@@ -441,7 +442,7 @@
     Map<String, LinkedLibraryBuilder> linkedLibraries = setupForLink(
         _linkerInputs.linkedLibraries,
         _linkerInputs.getUnit,
-        _linkerInputs.getDeclaredVariable);
+        _linkerInputs.declaredVariables);
     linker = new Linker(linkedLibraries, _linkerInputs.getDependency,
         _linkerInputs.getUnit, null, analysisOptions);
   }
@@ -481,11 +482,9 @@
       this._dependentLinkedLibraries,
       this._dependentUnlinkedUnits);
 
-  Set<String> get linkedLibraries => _uriToUnit.keys.toSet();
+  DeclaredVariables get declaredVariables => DeclaredVariables();
 
-  String getDeclaredVariable(String name) {
-    return null;
-  }
+  Set<String> get linkedLibraries => _uriToUnit.keys.toSet();
 
   LinkedLibrary getDependency(String absoluteUri) {
     Map<String, LinkedLibrary> sdkLibraries =
@@ -555,7 +554,7 @@
         linkerInputs.linkedLibraries,
         linkerInputs.getDependency,
         linkerInputs.getUnit,
-        linkerInputs.getDeclaredVariable,
+        linkerInputs.declaredVariables,
         analysisOptions);
     linkedLibraries.forEach(assembler.addLinkedLibrary);
     linkerInputs._uriToUnit.forEach((String uri, UnlinkedUnit unit) {
@@ -620,7 +619,7 @@
         _linkerInputs.linkedLibraries,
         _linkerInputs.getDependency,
         _linkerInputs.getUnit,
-        (name) => null,
+        DeclaredVariables(),
         analysisOptions)[_linkerInputs._testDartUri.toString()];
     expect(linked, isNotNull);
     _validateLinkedLibrary(linked);
diff --git a/pkg/analyzer_cli/lib/src/build_mode.dart b/pkg/analyzer_cli/lib/src/build_mode.dart
index d8df284..ca4002a 100644
--- a/pkg/analyzer_cli/lib/src/build_mode.dart
+++ b/pkg/analyzer_cli/lib/src/build_mode.dart
@@ -358,7 +358,7 @@
           libraryUris,
           getDependency,
           getUnit,
-          analysisDriver.declaredVariables.get,
+          analysisDriver.declaredVariables,
           analysisOptions);
       linkResult.forEach(assembler.addLinkedLibrary);
     });
diff --git a/pkg/dev_compiler/lib/src/analyzer/driver.dart b/pkg/dev_compiler/lib/src/analyzer/driver.dart
index 4728fb1..a4fd216 100644
--- a/pkg/dev_compiler/lib/src/analyzer/driver.dart
+++ b/pkg/dev_compiler/lib/src/analyzer/driver.dart
@@ -233,7 +233,7 @@
         libraryUris.toSet(),
         (uri) => summaryData.linkedMap[uri],
         (uri) => summaryData.unlinkedMap[uri] ?? uriToUnit[uri],
-        declaredVariables.get,
+        declaredVariables,
         analysisOptions);
     linkResult.forEach(assembler.addLinkedLibrary);