Reland "Add support for screen sharing with PipeWire on Wayland"

The content_unittests failure was caused by wrong path in the cfi
blacklist (when the files from x11 folder were moved to the linux
folder by this change).

Bug: chromium:682122
Change-Id: I4f7f6c5a73a981feeac18494749f85935e812981
Reviewed-on: https://webrtc-review.googlesource.com/c/110461
Commit-Queue: Tomáš Popela <tomas.popela@gmail.com>
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Reviewed-by: Brave Yao <braveyao@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#25621}
diff --git a/webrtc.gni b/webrtc.gni
index bba3369..f09ed64 100644
--- a/webrtc.gni
+++ b/webrtc.gni
@@ -9,6 +9,7 @@
 import("//build/config/features.gni")
 import("//build/config/mips.gni")
 import("//build/config/sanitizers/sanitizers.gni")
+import("//build/config/sysroot.gni")
 import("//build/config/ui.gni")
 import("//build_overrides/build.gni")
 
@@ -107,6 +108,9 @@
   # Set this to false to skip building code that requires X11.
   rtc_use_x11 = use_x11
 
+  # Set this to use PipeWire on the Wayland display server.
+  rtc_use_pipewire = false
+
   # Enable to use the Mozilla internal settings.
   build_with_mozilla = false
 
@@ -229,7 +233,8 @@
 rtc_opus_dir = "//third_party/opus"
 
 # Desktop capturer is supported only on Windows, OSX and Linux.
-rtc_desktop_capture_supported = is_win || is_mac || (is_linux && rtc_use_x11)
+rtc_desktop_capture_supported =
+    is_win || is_mac || (is_linux && (rtc_use_x11 || rtc_use_pipewire))
 
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