[gtk/wip/otte/build: 814/819] build: Set proper defaults for media backends

[Matthias Clasen <matthiasc src gnome org>]

commit a36b3c130e2e786aa92a9c1f1e84c9d61b5e23ff
Author: Benjamin Otte <otte redhat com>
Date:   Thu Apr 1 17:59:18 2021 +0200

    build: Set proper defaults for media backends
    
    GTK supports webm playback, which means a backend should always be
    compiled.
    
    The ffmpeg backend however is incomplete (no audio) and as such, we
    don't want people to end up with it accidentally.
    
    Since we don't want to drag an entire gstreamer build into our ci
    on MacOs, explicitly disable the gstreame media backend there.

 .gitlab-ci.yml    | 1 +
 meson_options.txt | 8 +++++---
 2 files changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index c100755896..8fddbcf284 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -172,6 +172,7 @@ macos:
     - meson -Dx11-backend=false
             -Dbroadway-backend=true
             -Dmacos-backend=true
+            -Dmedia-gstreamer=disabled
             -Dintrospection=disabled
             -Dcpp_std=c++11
             -Dpixman:tests=disabled
diff --git a/meson_options.txt b/meson_options.txt
index 402caec5fb..2223cb7964 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -26,15 +26,17 @@ option('macos-backend',
        description : 'Enable the macOS gdk backend (only when building on macOS)')
 
 # Media backends
+# For distros: GTK guarantees support for WebM video (VP8 and VP9), so a supported build
+# should provide that.
 
 option('media-ffmpeg',
        type: 'feature',
-       value: 'auto',
-       description : 'Build the ffmpeg media backend')
+       value: 'disabled',
+       description : 'Build the experimental ffmpeg media backend')
 
 option('media-gstreamer',
        type: 'feature',
-       value: 'auto',
+       value: 'enabled',
        description : 'Build the gstreamer media backend')
 
 # Print backends