[vala/staging] gstreamer: Update from 1.17.2+ git master

[Rico Tzschichholz <ricotz src gnome org>]

commit 098ef70fd53386a11c32e1dc81908ac821a5ca06
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Tue Aug 4 15:26:27 2020 +0200

    gstreamer: Update from 1.17.2+ git master

 vapi/gstreamer-1.0.vapi | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/vapi/gstreamer-1.0.vapi b/vapi/gstreamer-1.0.vapi
index 096fb408a..4358e2472 100644
--- a/vapi/gstreamer-1.0.vapi
+++ b/vapi/gstreamer-1.0.vapi
@@ -386,6 +386,9 @@ namespace Gst {
                [Version (since = "1.6")]
                public static Gst.Uri? from_string (string uri);
                [CCode (cheader_filename = "gst/gst.h")]
+               [Version (since = "1.18")]
+               public static Gst.Uri? from_string_escaped (string uri);
+               [CCode (cheader_filename = "gst/gst.h")]
                public static string? get_location (string uri);
                [CCode (cheader_filename = "gst/gst.h")]
                public static string? get_protocol (string uri);