Cache flushing implementation for the task model.

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

Index: pkg/analyzer/test/src/task/model_test.dart
diff --git a/pkg/analyzer/test/src/task/model_test.dart b/pkg/analyzer/test/src/task/model_test.dart
index 5fd31ec70250b27e6fd7ffc6839a006a0d9507d6..9a402a291d9fc3117a1a0eeee0e1ecc4aade5e81 100644
--- a/pkg/analyzer/test/src/task/model_test.dart
+++ b/pkg/analyzer/test/src/task/model_test.dart
@@ -19,6 +19,7 @@ main() {
   runReflectiveTests(AnalysisTaskTest);
   runReflectiveTests(ContributionPointImplTest);
   runReflectiveTests(ResultDescriptorImplTest);
+  runReflectiveTests(SimpleResultCachingPolicyTest);
   runReflectiveTests(TaskDescriptorImplTest);
 }
 
@@ -94,6 +95,13 @@ class ContributionPointImplTest extends EngineTestCase {
 
 @reflectiveTest
 class ResultDescriptorImplTest extends EngineTestCase {
+  test_create_withCachingPolicy() {
+    ResultCachingPolicy policy = new SimpleResultCachingPolicy(128, 16);
+    ResultDescriptorImpl result =
+        new ResultDescriptorImpl('result', null, cachingPolicy: policy);
+    expect(result.cachingPolicy, same(policy));
+  }
+
   test_create_withContribution() {
     CompositeResultDescriptorImpl point =
         new CompositeResultDescriptorImpl('point');
@@ -104,6 +112,14 @@ class ResultDescriptorImplTest extends EngineTestCase {
     expect(contributors, unorderedEquals([result]));
   }
 
+  test_create_withoutCachingPolicy() {
+    ResultDescriptorImpl result = new ResultDescriptorImpl('result', null);
+    ResultCachingPolicy cachingPolicy = result.cachingPolicy;
+    expect(cachingPolicy, isNotNull);
+    expect(cachingPolicy.maxActiveSize, -1);
+    expect(cachingPolicy.maxIdleSize, -1);
+  }
+
   test_create_withoutContribution() {
     expect(new ResultDescriptorImpl('name', null), isNotNull);
   }
@@ -123,6 +139,16 @@ class ResultDescriptorImplTest extends EngineTestCase {
 }
 
 @reflectiveTest
+class SimpleResultCachingPolicyTest extends EngineTestCase {
+  test_create() {
+    ResultCachingPolicy policy = new SimpleResultCachingPolicy(256, 32);
+    expect(policy.maxActiveSize, 256);
+    expect(policy.maxIdleSize, 32);
+    expect(policy.measure(null), 1);
+  }
+}
+
+@reflectiveTest
 class TaskDescriptorImplTest extends EngineTestCase {
   test_create() {
     String name = 'name';