Prevent creation of Drive initiated message hosts when flag is off

Bug: 1150731
Change-Id: Ia55338e87250fd28f19c28343b6bf3a65dfacf10
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2549160
Commit-Queue: Austin Tankiang <austinct@chromium.org>
Reviewed-by: Sergei Datsenko <dats@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830090}

chrome/browser/chromeos/drive/drivefs_native_message_host.cc

@@ -161,6 +161,10 @@ CreateDriveFsInitiatedNativeMessageHost(
     mojo::PendingReceiver<drivefs::mojom::NativeMessagingPort>
         extension_receiver,
     mojo::PendingRemote<drivefs::mojom::NativeMessagingHost> drivefs_remote) {
+  if (!base::FeatureList::IsEnabled(
+          chromeos::features::kDriveFsBidirectionalNativeMessaging)) {
+    return nullptr;
+  }
   return std::make_unique<DriveFsNativeMessageHost>(
       std::move(extension_receiver), std::move(drivefs_remote));
 }
@@ -196,6 +200,11 @@ ConnectToDriveFsNativeMessageExtension(
       extensions::MessageService::Get(profile);
   auto native_message_host = CreateDriveFsInitiatedNativeMessageHost(
       std::move(extension_receiver), std::move(drivefs_remote));
+  if (!native_message_host) {
+    return drivefs::mojom::DriveFsDelegate::ExtensionConnectionStatus::
+        kExtensionNotFound;
+  }
+
   auto native_message_port = std::make_unique<extensions::NativeMessagePort>(
       message_service->GetChannelDelegate(), port_id,
       std::move(native_message_host));

chrome/browser/chromeos/drive/drivefs_native_message_host_unittest.cc

@@ -72,13 +72,14 @@ class DriveFsNativeMessageHostTest
               (const std::string& message),
               (override));
 
-  base::test::ScopedFeatureList scoped_feature_list_;
   base::test::TaskEnvironment task_environment_;
   drivefs::mojom::ExtensionConnectionParamsPtr params_;
   mojo::Receiver<drivefs::mojom::NativeMessagingHost> receiver_{this};
   mojo::Remote<drivefs::mojom::NativeMessagingPort> extension_port_;
 
  private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+
   DISALLOW_COPY_AND_ASSIGN(DriveFsNativeMessageHostTest);
 };
 
@@ -159,5 +160,26 @@ TEST_F(DriveFsNativeMessageHostTest, Error) {
   run_loop.Run();
 }
 
+class DriveFsNativeMessageHostTestWithoutFlag
+    : public DriveFsNativeMessageHostTest {
+ public:
+  DriveFsNativeMessageHostTestWithoutFlag() {
+    scoped_feature_list_.InitAndDisableFeature(
+        chromeos::features::kDriveFsBidirectionalNativeMessaging);
+  }
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
+
+  DISALLOW_COPY_AND_ASSIGN(DriveFsNativeMessageHostTestWithoutFlag);
+};
+
+TEST_F(DriveFsNativeMessageHostTestWithoutFlag,
+       DriveFsCannotInitiateMessaging) {
+  ASSERT_FALSE(CreateDriveFsInitiatedNativeMessageHost(
+      extension_port_.BindNewPipeAndPassReceiver(),
+      receiver_.BindNewPipeAndPassRemote()));
+}
+
 }  // namespace
 }  // namespace drive