Add a Display and ContextProvider concept to mojom, use to recreate

services/native_viewport/BUILD.gn

Index: services/native_viewport/BUILD.gn
diff --git a/services/native_viewport/BUILD.gn b/services/native_viewport/BUILD.gn
index 61ec54090e3d6e5d12ea28ed7d66e5abfe042f23..647a88e002adb06d98fd5a5b75915a9236abc505 100644
--- a/services/native_viewport/BUILD.gn
+++ b/services/native_viewport/BUILD.gn
@@ -57,6 +57,8 @@ source_set("lib") {
   sources = [
     "native_viewport_impl.cc",
     "native_viewport_impl.h",
+    "onscreen_context_provider.cc",
+    "onscreen_context_provider.h",
     "platform_viewport.h",
     "platform_viewport_android.cc",
     "platform_viewport_android.h",
@@ -65,8 +67,6 @@ source_set("lib") {
     "platform_viewport_stub.cc",
     "platform_viewport_win.cc",
     "platform_viewport_x11.cc",
-    "viewport_surface.cc",
-    "viewport_surface.h",
   ]
 
   if (!is_ios) {
@@ -75,21 +75,15 @@ source_set("lib") {
 
   deps = [
     "//base",
-    "//cc/surfaces",
-    "//cc/surfaces:surface_id",
     "//gpu/command_buffer/service",
     "//mojo/application",
     "//mojo/common",
     "//mojo/converters/geometry",
     "//mojo/converters/input_events",
-    "//mojo/converters/surfaces",
     "//mojo/environment:chromium",
     "//services/gles2",
     "//mojo/services/geometry/public/interfaces",
-    "//mojo/services/gpu/public/interfaces",
     "//mojo/services/native_viewport/public/interfaces",
-    "//mojo/services/surfaces/public/cpp",
-    "//mojo/services/surfaces/public/interfaces",
     "//ui/events",
     "//ui/events/platform",
     "//ui/gfx",