Make --enable-slimming-paint-v2 enable --enable-layer-lists

content/browser/renderer_host/render_process_host_impl.cc

Index: content/browser/renderer_host/render_process_host_impl.cc
diff --git a/content/browser/renderer_host/render_process_host_impl.cc b/content/browser/renderer_host/render_process_host_impl.cc
index dc2f91b48d2f6c51019369ede5ac168eda7a8622..796f5d4f4525bdb5f452167228cbb93b413baf80 100644
--- a/content/browser/renderer_host/render_process_host_impl.cc
+++ b/content/browser/renderer_host/render_process_host_impl.cc
@@ -1476,6 +1476,11 @@ static void AppendCompositorCommandLineFlags(base::CommandLine* command_line) {
   GpuDataManagerImpl* gpu_data_manager = GpuDataManagerImpl::GetInstance();
   DCHECK(gpu_data_manager);
   gpu_data_manager->AppendRendererCommandLine(command_line);
+
+  // Slimming Paint v2 implies layer lists in the renderer.
+  if (base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableSlimmingPaintV2))
+    command_line->AppendSwitch(cc::switches::kEnableLayerLists);
 }
 
 void RenderProcessHostImpl::AppendRendererCommandLine(