electron/patches/common/chromium/compositor_delegate.patch

diff --git a/content/browser/compositor/gpu_process_transport_factory.cc b/content/browser/compositor/gpu_process_transport_factory.cc
index e679dbb02a81..d90a276fc0e1 100644
--- a/content/browser/compositor/gpu_process_transport_factory.cc
+++ b/content/browser/compositor/gpu_process_transport_factory.cc
@@ -507,10 +507,20 @@ void GpuProcessTransportFactory::EstablishedGpuChannel(
         // surfaces as they are not following the correct mode.
         DisableGpuCompositing(compositor.get());
       }
+
+      std::unique_ptr<viz::SoftwareOutputDevice> output_device;
+      if (compositor->delegate()) {
+        output_device = compositor->delegate()->CreateSoftwareOutputDevice(
+            compositor.get());
+      }
+      if (!output_device) {
+        output_device = CreateSoftwareOutputDevice(compositor->widget(),
+                                                   compositor->task_runner());
+      }
+
       display_output_surface =
           std::make_unique<SoftwareBrowserCompositorOutputSurface>(
-              CreateSoftwareOutputDevice(compositor->widget(),
-                                         compositor->task_runner()),
+              std::move(output_device),
               std::move(vsync_callback));
     } else {
       DCHECK(context_provider);
diff --git a/ui/compositor/compositor.h b/ui/compositor/compositor.h
index eb250697ebd6..36be87675e9a 100644
--- a/ui/compositor/compositor.h
+++ b/ui/compositor/compositor.h
@@ -24,6 +24,7 @@
 #include "components/viz/common/surfaces/frame_sink_id.h"
 #include "components/viz/common/surfaces/local_surface_id.h"
 #include "components/viz/host/host_frame_sink_client.h"
+#include "components/viz/service/display/software_output_device.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/skia/include/core/SkMatrix44.h"
 #include "ui/compositor/compositor_animation_observer.h"
@@ -183,6 +184,15 @@ class COMPOSITOR_EXPORT ContextFactory {
   virtual void RemoveObserver(ContextFactoryObserver* observer) = 0;
 };
 
+class COMPOSITOR_EXPORT CompositorDelegate {
+ public:
+  virtual std::unique_ptr<viz::SoftwareOutputDevice> CreateSoftwareOutputDevice(
+      ui::Compositor* compositor) = 0;
+
+ protected:
+  virtual ~CompositorDelegate() {}
+};
+
 // Compositor object to take care of GPU painting.
 // A Browser compositor object is responsible for generating the final
 // displayable form of pixels comprising a single widget's contents. It draws an
@@ -222,6 +232,9 @@ class COMPOSITOR_EXPORT Compositor : public cc::LayerTreeHostClient,
   // Schedules a redraw of the layer tree associated with this compositor.
   void ScheduleDraw();
 
+  CompositorDelegate* delegate() const { return delegate_; }
+  void SetDelegate(CompositorDelegate* delegate) { delegate_ = delegate; }
+
   // Sets the root of the layer tree drawn by this Compositor. The root layer
   // must have no parent. The compositor's root layer is reset if the root layer
   // is destroyed. NULL can be passed to reset the root layer, in which case the
@@ -447,6 +460,8 @@ class COMPOSITOR_EXPORT Compositor : public cc::LayerTreeHostClient,
   ui::ContextFactory* context_factory_;
   ui::ContextFactoryPrivate* context_factory_private_;
 
+  CompositorDelegate* delegate_ = nullptr;
+
   // The root of the Layer tree drawn by this compositor.
   Layer* root_layer_ = nullptr;