avoid stringstream if reasonable

src/client/videomanager.cpp

src/ice_transport.cpp

src/jamidht/gitserver.cpp

src/jamidht/server_account_manager.cpp

src/media/media_recorder.cpp

src/media/video/iosvideo/video_device_impl.cpp

src/media/video/uwpvideo/video_device_impl.cpp

src/media/video/v4l2/video_device_impl.cpp