Consolidate OutputSurface constructors into GL vs Vulkan.

ui/compositor/test/in_process_context_factory.cc

Index: ui/compositor/test/in_process_context_factory.cc
diff --git a/ui/compositor/test/in_process_context_factory.cc b/ui/compositor/test/in_process_context_factory.cc
index 735d3600b4db70f0bad19b5b0e363e85f894c902..6ad88574d86fd854f2848a9b35a65982503a293b 100644
--- a/ui/compositor/test/in_process_context_factory.cc
+++ b/ui/compositor/test/in_process_context_factory.cc
@@ -49,7 +49,7 @@ class DirectOutputSurface : public cc::OutputSurface {
       const scoped_refptr<cc::ContextProvider>& context_provider,
       const scoped_refptr<cc::ContextProvider>& worker_context_provider,
       std::unique_ptr<cc::BeginFrameSource> begin_frame_source)
-      : cc::OutputSurface(context_provider, worker_context_provider),
+      : cc::OutputSurface(context_provider, worker_context_provider, nullptr),
         begin_frame_source_(std::move(begin_frame_source)),
         weak_ptr_factory_(this) {}