chromium-fourier r2 + firefox-fourier 150.0.1 + KWIN_PIVOT.md

chromium-fourier:
- patch 3/3 nv12-external-oes-on-modifier-external-only.patch — adds
  NativePixmapEGLBinding::ModifierRequiresExternalOES helper, extends
  OzoneImageGLTexturesHolder::GetBinding to honor EGL external_only
  flag for NV12 dmabufs on panfrost / panthor. Validated on ohm
  (RK3566 hantro mainline 6.19.10): bbb_1080p30_h264.mp4 plays at
  34.7 % combined CPU vs ~131 % pre-patch baseline (~3.8x).
- PKGBUILD pkgrel 1->2, source array + sha256sums + prepare() hook for
  patch 4, patch numbering 1/2,2/2 -> 1/3,2/3,3/3.
- NEXT.md appended with 2026-04-28 section: patch 4 design, validation
  log, KWin GL_ALPHA bug pinpoint (preexisting since 2026-03-06,
  affects every wayland video client; unrelated to chromium-fourier),
  device-renumbering note (/dev/video1 = encoder post-reboot).
- KWIN_PIVOT.md: 4-phase plan to identify and patch KWin's
  glTexImage2D(internalFormat=GL_ALPHA) site, ohm-only test plan,
  scope discipline.
- patches/ now tracked (compiler-rt-adjust-paths, enable-v4l2,
  wayland-allow-direct-egl-gles2, nv12-external-oes); the dead-end
  chromeos-pipeline-bypass.patch removed.

firefox-fourier:
- 4 patches (gfxinfo v4l2 stateless fourccs, libwrapper hwdevice ctx,
  ffmpegvideo v4l2-request route, prefs v4l2-request default).
- PKGBUILD bumped to firefox 150.0.1, Arch toolchain glue patches
  layered in, mozconfig with --without-wasm-sandboxed-libraries for
  ALARM, package() launcher fix (rm -f symlink before cat > to avoid
  ENOENT through the dangling /usr/local symlink mach install drops).
- 150.0.1-1-aarch64.pkg.tar.zst built on boltzmann (95 MB), pending
  fresnel power-on for V4L2 stateless validation on RK3399.

arch/firefox-fourier/patches/0002-libwrapper-hwdevice-ctx-create.patch

@@ -0,0 +1,52 @@
+From: Markus Fritsche <mfritsche@reauktion.de>
+Subject: [PATCH 2/4] dom/media/platforms/ffmpeg: wrap
+ av_hwdevice_ctx_create
+Date: 2026-04-27
+
+Background
+----------
+`FFmpegLibWrapper` already wraps `av_hwdevice_ctx_alloc` (no device
+path) and `av_hwdevice_ctx_init`, used by the VAAPI codepath which
+discovers the DRM device implicitly. The v4l2_request hwaccel needs
+the *path-aware* constructor `av_hwdevice_ctx_create`, which lets the
+caller pass `"/dev/dri/renderD128"` (or similar) directly when
+creating an `AV_HWDEVICE_TYPE_DRM` context. libavcodec then binds the
+v4l2_request hwaccel internally based on the codec's `hw_configs`.
+
+This patch adds the function pointer + the `AV_FUNC_OPTION_SILENT`
+registration. Same versioning as the other `av_hwdevice_ctx_*`
+wrappers (libavutil 58–62). No callers yet — patch 3/4
+(FFmpegVideoDecoder routing) consumes it.
+
+Bug 1969297.
+
+diff --git a/dom/media/platforms/ffmpeg/FFmpegLibWrapper.h b/dom/media/platforms/ffmpeg/FFmpegLibWrapper.h
+--- a/dom/media/platforms/ffmpeg/FFmpegLibWrapper.h
++++ b/dom/media/platforms/ffmpeg/FFmpegLibWrapper.h
+@@ -177,6 +177,11 @@
+   // libavutil >= 58
+   AVBufferRef* (*av_hwdevice_ctx_alloc)(int);
+   int (*av_hwdevice_ctx_init)(AVBufferRef* ref);
++  // firefox-fourier: device-path-aware constructor needed to bind a
++  // DRM hwdevice (AV_HWDEVICE_TYPE_DRM) to /dev/dri/renderD* for the
++  // libavcodec v4l2_request hwaccel.
++  int (*av_hwdevice_ctx_create)(AVBufferRef** device_ctx, int type,
++                                const char* device, void* opts, int flags);
+   AVBufferRef* (*av_hwframe_ctx_alloc)(AVBufferRef* device_ctx);
+   int (*av_hwframe_ctx_init)(AVBufferRef* ref);
+   AVBufferRef* (*av_buffer_ref)(AVBufferRef* buf);
+diff --git a/dom/media/platforms/ffmpeg/FFmpegLibWrapper.cpp b/dom/media/platforms/ffmpeg/FFmpegLibWrapper.cpp
+--- a/dom/media/platforms/ffmpeg/FFmpegLibWrapper.cpp
++++ b/dom/media/platforms/ffmpeg/FFmpegLibWrapper.cpp
+@@ -293,6 +293,11 @@ FFmpegLibWrapper::LinkResult FFmpegLibWrapper::Link() {
+                         AV_FUNC_AVUTIL_58 | AV_FUNC_AVUTIL_59 |
+                             AV_FUNC_AVUTIL_60 | AV_FUNC_AVUTIL_61 |
+                             AV_FUNC_AVUTIL_62)
++  // firefox-fourier: see comment in FFmpegLibWrapper.h
++  AV_FUNC_OPTION_SILENT(av_hwdevice_ctx_create,
++                        AV_FUNC_AVUTIL_58 | AV_FUNC_AVUTIL_59 |
++                            AV_FUNC_AVUTIL_60 | AV_FUNC_AVUTIL_61 |
++                            AV_FUNC_AVUTIL_62)
+   AV_FUNC_OPTION_SILENT(
+       av_buffer_ref, AV_FUNC_AVUTIL_58 | AV_FUNC_AVUTIL_59 | AV_FUNC_AVUTIL_60 |
+                          AV_FUNC_AVUTIL_61 | AV_FUNC_AVUTIL_62)