drive: Stop making multiple GetAppList() requests from DriveAppRegistry

chrome/browser/chromeos/drive/drive_app_registry_unittest.cc

Index: chrome/browser/chromeos/drive/drive_app_registry_unittest.cc
diff --git a/chrome/browser/chromeos/drive/drive_app_registry_unittest.cc b/chrome/browser/chromeos/drive/drive_app_registry_unittest.cc
index 6228f425900929b429873627723c4d0175283bca..eacfae625b7da832653edfd74e289c0b5a833deb 100644
--- a/chrome/browser/chromeos/drive/drive_app_registry_unittest.cc
+++ b/chrome/browser/chromeos/drive/drive_app_registry_unittest.cc
@@ -30,8 +30,6 @@ class DriveAppRegistryTest : public testing::Test {
                                       base::MessageLoopProxy::current().get()));
 
     web_apps_registry_.reset(new DriveAppRegistry(scheduler_.get()));
-    web_apps_registry_->Update();
-    base::RunLoop().RunUntilIdle();
   }
 
   bool VerifyApp(const ScopedVector<DriveAppInfo>& list,
@@ -54,7 +52,7 @@ class DriveAppRegistryTest : public testing::Test {
       }
     }
     EXPECT_TRUE(found) << "Unable to find app with web_store_id "
-        << web_store_id;
+                       << web_store_id;
     return found;
   }
 
@@ -66,6 +64,9 @@ class DriveAppRegistryTest : public testing::Test {
 };
 
 TEST_F(DriveAppRegistryTest, LoadAndFindDriveApps) {
+  web_apps_registry_->Update();
+  base::RunLoop().RunUntilIdle();
+
   // Find by primary extension 'exe'.
   ScopedVector<DriveAppInfo> ext_results;
   base::FilePath ext_file(FILE_PATH_LITERAL("drive/file.exe"));
@@ -91,4 +92,17 @@ TEST_F(DriveAppRegistryTest, LoadAndFindDriveApps) {
             "Drive app 1", "", false);
 }
 
+TEST_F(DriveAppRegistryTest, MultipleUpdate) {
+  // Call Update().
+  web_apps_registry_->Update();
+
+  // Call Update() again.
+  // This call should be ignored because there is already an ongoing update.
+  web_apps_registry_->Update();
+
+  // The app list should be loaded only once.
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(1, fake_drive_service_->app_list_load_count());
+}
+
 }  // namespace drive