Create a task in the new task model to compute constant dependencies.

pkg/analyzer/test/src/task/dart_test.dart

Index: pkg/analyzer/test/src/task/dart_test.dart
diff --git a/pkg/analyzer/test/src/task/dart_test.dart b/pkg/analyzer/test/src/task/dart_test.dart
index 70e76f97260613aa096368c431a3716fc3d0beca..e62b3de0b0b02770dd0e0ce6a234cd4c42670f1c 100644
--- a/pkg/analyzer/test/src/task/dart_test.dart
+++ b/pkg/analyzer/test/src/task/dart_test.dart
@@ -33,6 +33,7 @@ main() {
   runReflectiveTests(BuildLibraryElementTaskTest);
   runReflectiveTests(BuildPublicNamespaceTaskTest);
   runReflectiveTests(BuildTypeProviderTaskTest);
+  runReflectiveTests(ComputeConstantDependenciesTaskTest);
   runReflectiveTests(ContainingLibrariesTaskTest);
   runReflectiveTests(DartErrorsTaskTest);
   runReflectiveTests(GatherUsedImportedElementsTaskTest);
@@ -1187,6 +1188,29 @@ class BuildTypeProviderTaskTest extends _AbstractDartTaskTest {
 }
 
 @reflectiveTest
+class ComputeConstantDependenciesTaskTest extends _AbstractDartTaskTest {
+  test_perform() {
+    Source source = newSource('/test.dart', '''
+const x = y;
+const y = 1;
+''');
+    // First compute the library element for the source.
+    _computeResult(source, LIBRARY_ELEMENT1);
+    LibraryElement libraryElement = outputs[LIBRARY_ELEMENT1];
+    // Find the elements for the constant x and y.

[Brian Wilkerson, 2015/05/07 22:46:59]

"constant" --> "constants"

[Paul Berry, 2015/05/08 00:24:35]

Done.

+    List<PropertyAccessorElement> accessors =
+        libraryElement.definingCompilationUnit.accessors;
+    Element x = accessors.firstWhere((PropertyAccessorElement accessor) =>
+        accessor.isGetter && accessor.name == 'x').variable;
+    Element y = accessors.firstWhere((PropertyAccessorElement accessor) =>
+        accessor.isGetter && accessor.name == 'y').variable;
+    // Now compute the dependencies for x, and check that it is the list [y].
+    _computeResult(x, CONSTANT_DEPENDENCIES);
+    expect(outputs[CONSTANT_DEPENDENCIES], [y]);
+  }
+}
+
+@reflectiveTest
 class ContainingLibrariesTaskTest extends _AbstractDartTaskTest {
   test_buildInputs() {
     Map<String, TaskInput> inputs =