exo: Add Surface::SetBufferScale.

components/exo/wayland/server.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/exo/wayland/server.h"
 
 #include <linux/input.h>
 #include <wayland-server-core.h>
 #include <wayland-server-protocol-core.h>
 #include <xdg-shell-unstable-v5-server-protocol.h>
@@ skipping 157 matching lines @@
 
 void surface_set_buffer_transform(wl_client* client,
                                   wl_resource* resource,
                                   int transform) {
   NOTIMPLEMENTED();
 }
 
 void surface_set_buffer_scale(wl_client* client,
                               wl_resource* resource,
                               int32_t scale) {
-  NOTIMPLEMENTED();
+  if (scale < 1) {
+    wl_resource_post_error(resource, WL_SURFACE_ERROR_INVALID_SCALE,
+                           "buffer scale must be at least one "
+                           "('%d' specified)",
+                           scale);
+    return;
+  }
+
+  GetUserDataAs<Surface>(resource)->SetBufferScale(scale);
 }
 
 const struct wl_surface_interface surface_implementation = {
     surface_destroy,
     surface_attach,
     surface_damage,
     surface_frame,
     surface_set_opaque_region,
     surface_set_input_region,
     surface_commit,
@@ skipping 1253 matching lines @@
   DCHECK(event_loop);
   wl_event_loop_dispatch(event_loop, timeout.InMilliseconds());
 }
 
 void Server::Flush() {
   wl_display_flush_clients(wl_display_.get());
 }
 
 }  // namespace wayland
 }  // namespace exo