frontends (tools/webrtc): implement screensharing for Wayland + bug fixes: - Freedesktop Desktop Screenshare port is now used when Wayland is detected (needs `xdg-desktop-portal` with the implementation corresponding to desktop environment). - Add a binding feature to feedback state to application (e.g. if desktop sharing is cancelled from desktop environment, or at portal's permission request level). - fix misnaming of video source (was wrongly named `camera` instead of `video`). - fix desktop sharing pad selection in `input-selector` when it has been added once, then removed, then added again. rel 434

# Minimal makefile for Sphinx documentation
#

# You can set these variables from the command line.
SPHINXOPTS    =
SPHINXBUILD   = sphinx-build
SOURCEDIR     = .
BUILDDIR      = .build

# Put it first so that "make" without argument is like "make help".
help:
	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

.PHONY: help Makefile

# Catch-all target: route all unknown targets to Sphinx using the new
# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
%: Makefile
	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)