Phase 0: browser X11-overlay inventory + mpv reference cell + tooling installs

Source-level verdict: no browser in the matrix has a code path to hand NV12 to the X server for plane scanout. Chromium ozone-x11 wires StubOverlayManager (ozone_platform_x11.cc:262); Brave 147 + chromium-fourier 149 inherit unchanged. Firefox WindowSurfaceX11 is RGB-only. The campaign's load-bearing hypothesis is structurally weakened — what the X11 cells will measure for browsers is KWin's per-frame RGB-recomposite cost, not the original "force-GL-composite of NV12" framing. mpv --vo=xv becomes the matrix's only direct test of the operator-supplied mechanism. Matrix updated: 12 cells -> 16 cells (+8 mpv VO sub-points). revert.log entries 1-5 capture all package + per-user state mutations from this turn (measurement tools, openbox, XFCE + xfwm4-no-comp pre-seed, firefox + AUR xtrace, XFCE rotation + touchscreen mapping); single SSH-driveable revert chain returns ohm to its pre-campaign 1169-package state. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-03 11:14:46 +00:00
parent 5d34a957ee
commit d2e11be430
30 changed files with 13176 additions and 35 deletions
@@ -0,0 +1,46 @@
+// Copyright 2015 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_OZONE_PUBLIC_OVERLAY_MANAGER_OZONE_H_
+#define UI_OZONE_PUBLIC_OVERLAY_MANAGER_OZONE_H_
+
+#include <memory>
+
+#include "ui/gfx/native_ui_types.h"
+
+namespace ui {
+
+class OverlayCandidatesOzone;
+
+// Responsible for providing the oracles used to decide when overlays can be
+// used.
+class OverlayManagerOzone {
+ public:
+  virtual ~OverlayManagerOzone() {}
+
+  // Get the hal struct to check for overlay support.
+  virtual std::unique_ptr<OverlayCandidatesOzone> CreateOverlayCandidates(
+      gfx::AcceleratedWidget w) = 0;
+
+  bool allow_sync_and_real_buffer_page_flip_testing() const {
+    return allow_sync_and_real_buffer_page_flip_testing_;
+  }
+
+  // Tell the manager that the overlay delegation is enabled. This is only
+  // useful for Wayland as checking for overlay support depends on
+  // features::IsDelegatedCompositingEnabled, which cannot be accessed from
+  // //ui/ozone.
+  // TODO(msisov, petermcneeley): remove this once Wayland uses only delegated
+  // context.
+  virtual void SetContextDelegated() {}
+
+ protected:
+  // TODO(fangzhoug): Some Chrome OS boards still use the legacy video decoder.
+  // Remove this once ChromeOSVideoDecoder is on everywhere.
+  bool allow_sync_and_real_buffer_page_flip_testing_ = false;
+};
+
+}  // namespace ui
+
+#endif  // UI_OZONE_PUBLIC_OVERLAY_MANAGER_OZONE_H_