avoid the neeed to escape url passed to gstreamer

Change-Id: I13d0cee911a3c9af99b494dde16b8d51f78d954a
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/158889
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolan.mcnamara@collabora.com>
diff --git a/avmedia/source/gstreamer/gstframegrabber.cxx b/avmedia/source/gstreamer/gstframegrabber.cxx
index a3b4b3a..7a65751 100644
--- a/avmedia/source/gstreamer/gstframegrabber.cxx
+++ b/avmedia/source/gstreamer/gstframegrabber.cxx
@@ -50,10 +50,9 @@ void FrameGrabber::disposePipeline()

FrameGrabber::FrameGrabber( std::u16string_view rURL )
{
    gchar *pPipelineStr = g_strdup_printf(
        "uridecodebin uri=\"%s\" ! videoconvert ! videoscale ! appsink "
        "name=sink caps=\"video/x-raw,format=RGB,pixel-aspect-ratio=1/1\"",
        OUStringToOString( rURL, RTL_TEXTENCODING_UTF8 ).getStr() );
    const char pPipelineStr[] =
        "uridecodebin name=source ! videoconvert ! videoscale ! appsink "
        "name=sink caps=\"video/x-raw,format=RGB,pixel-aspect-ratio=1/1\"";

    GError *pError = nullptr;
    mpPipeline = gst_parse_launch( pPipelineStr, &pError );
@@ -64,6 +63,12 @@ FrameGrabber::FrameGrabber( std::u16string_view rURL )
    }

    if( mpPipeline ) {

        if (GstElement *pUriDecode = gst_bin_get_by_name(GST_BIN(mpPipeline), "source"))
            g_object_set(pUriDecode, "uri", OUStringToOString(rURL, RTL_TEXTENCODING_UTF8).getStr(), nullptr);
        else
            g_warning("Missing 'source' element in gstreamer pipeline");

        // pre-roll
        switch( gst_element_set_state( mpPipeline, GST_STATE_PAUSED ) ) {
        case GST_STATE_CHANGE_FAILURE: