Better way to implement FrameConnectedBluetoothDevicesTest

content/browser/bluetooth/web_bluetooth_service_impl.h

Index: content/browser/bluetooth/web_bluetooth_service_impl.h
diff --git a/content/browser/bluetooth/web_bluetooth_service_impl.h b/content/browser/bluetooth/web_bluetooth_service_impl.h
index 44e1858594e1486fefd0dc2ec68506b72c5a9fc5..c93ca9194317521784c5da7ee25b6a1e3fc66ae5 100644
--- a/content/browser/bluetooth/web_bluetooth_service_impl.h
+++ b/content/browser/bluetooth/web_bluetooth_service_impl.h
@@ -43,9 +43,10 @@ class RenderProcessHost;
 // from the renderer when the first Web Bluetooth API request is handled.
 // RenderFrameHostImpl will create an instance of this class and keep
 // ownership of it.
-class WebBluetoothServiceImpl : public blink::mojom::WebBluetoothService,
-                                public WebContentsObserver,
-                                public device::BluetoothAdapter::Observer {
+class CONTENT_EXPORT WebBluetoothServiceImpl
+    : public NON_EXPORTED_BASE(blink::mojom::WebBluetoothService),
+      public WebContentsObserver,
+      public device::BluetoothAdapter::Observer {
  public:
   // |render_frame_host|: The RFH that owns this instance.
   // |request|: The instance will be bound to this request's pipe.
@@ -57,6 +58,7 @@ class WebBluetoothServiceImpl : public blink::mojom::WebBluetoothService,
   void SetClientConnectionErrorHandler(base::Closure closure);
 
  private:
+  friend class FrameConnectedBluetoothDevicesTest;
   typedef base::Callback<void(device::BluetoothDevice*)>
       PrimaryServicesRequestCallback;