Integrate InstanceID with GCM crypto provider

components/gcm_driver/instance_id/instance_id_driver_unittest.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/gcm_driver/instance_id/instance_id_driver.h"
 
 #include <stddef.h>
 
 #include <cmath>
 
@@ skipping 102 matching lines @@
 }
 
 InstanceIDDriverTest::~InstanceIDDriverTest() {
 }
 
 void InstanceIDDriverTest::SetUp() {
   gcm_driver_.reset(new FakeGCMDriverForInstanceID);
   RecreateInstanceIDDriver();
 }
 
-void InstanceIDDriverTest::TearDown() {}
+void InstanceIDDriverTest::TearDown() {
+  driver_.reset();
+  gcm_driver_.reset();
+  // |gcm_driver_| owns a GCMKeyStore that owns a ProtoDatabaseImpl whose
+  // destructor deletes the underlying LevelDB on the task runner.
+  base::RunLoop().RunUntilIdle();
+}
 
 void InstanceIDDriverTest::RecreateInstanceIDDriver() {
   driver_.reset(new InstanceIDDriver(gcm_driver_.get()));
 }
 
 void InstanceIDDriverTest::WaitForAsyncOperation() {
   // No need to wait if async operation is not needed.
   if (async_operation_completed_)
     return;
   base::RunLoop run_loop;
@@ skipping 230 matching lines @@
       GetToken(instance_id, kAuthorizedEntity1, kScope2, options);
   EXPECT_FALSE(new_token1.empty());
   EXPECT_NE(token1, new_token1);
 
   // The other token is not affected by the deletion.
   EXPECT_EQ(token2,
             GetToken(instance_id, kAuthorizedEntity2, kScope1, options));
 }
 
 }  // namespace instance_id