mus: Embed the new surface in WindowPortMus::AllocateLocalSurfaceId

Seems like we don't embed the LocalSurfaceId allocated in
WindowPortMus::AllocateLocalSurfaceId with --mash. Embed it.

Bug: 807448
Change-Id: Id4c03c01d714de010a8306fc97bcd1a98dfaa3cb
Reviewed-on: https://chromium-review.googlesource.com/895926
Commit-Queue: Saman Sami <samans@chromium.org>
Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534176}

ui/aura/mus/client_surface_embedder.cc

@@ -94,4 +94,9 @@ void ClientSurfaceEmbedder::UpdateSizeAndGutters() {
   window_->layer()->StackAtTop(surface_layer_.get());
 }
 
+const viz::SurfaceId& ClientSurfaceEmbedder::GetPrimarySurfaceIdForTesting()
+    const {
+  return *surface_layer_->GetPrimarySurfaceId();
+}
+
 }  // namespace aura

ui/aura/mus/client_surface_embedder.h

@@ -9,16 +9,14 @@
 
 #include "base/macros.h"
 #include "components/viz/common/surfaces/surface_info.h"
+#include "ui/aura/aura_export.h"
+#include "ui/compositor/layer.h"
 #include "ui/gfx/geometry/insets.h"
 
 namespace gfx {
 class Insets;
 }
 
-namespace ui {
-class Layer;
-}
-
 namespace aura {
 
 class Window;
@@ -26,7 +24,7 @@ class Window;
 // Used by WindowPortMus when it is embedding a client. Responsible for setting
 // up layers containing content from the client, parenting them to the window's
 // layer, and updating them when the client submits new surfaces.
-class ClientSurfaceEmbedder {
+class AURA_EXPORT ClientSurfaceEmbedder {
  public:
   // TODO(fsamuel): Insets might differ when the window is maximized. We should
   // deal with that case as well.
@@ -51,6 +49,8 @@ class ClientSurfaceEmbedder {
 
   ui::Layer* BottomGutterForTesting() { return bottom_gutter_.get(); }
 
+  const viz::SurfaceId& GetPrimarySurfaceIdForTesting() const;
+
  private:
   // The window which embeds the client.
   Window* window_;

ui/aura/mus/window_port_mus.cc

@@ -403,6 +403,7 @@ WindowPortMus::ChangeSource WindowPortMus::OnTransientChildRemoved(
 
 void WindowPortMus::AllocateLocalSurfaceId() {
   local_surface_id_ = parent_local_surface_id_allocator_.GenerateId();
+  UpdatePrimarySurfaceId();
 }
 
 const viz::LocalSurfaceId& WindowPortMus::GetLocalSurfaceId() {

ui/aura/mus/window_port_mus_unittest.cc

@@ -7,6 +7,7 @@
 #include "components/viz/client/client_layer_tree_frame_sink.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/aura/local/layer_tree_frame_sink_local.h"
+#include "ui/aura/mus/client_surface_embedder.h"
 #include "ui/aura/test/aura_test_base.h"
 #include "ui/aura/window.h"
 #include "ui/base/ui_base_switches_util.h"
@@ -55,4 +56,24 @@ TEST_F(WindowPortMusTest, LayerTreeFrameSinkGetsCorrectLocalSurfaceId) {
   EXPECT_EQ(frame_sink_local_surface_id, local_surface_id);
 }
 
+TEST_F(WindowPortMusTest, ClientSurfaceEmbedderUpdatesLayer) {
+  // If mus is not hosting viz, we don't have ClientSurfaceEmbedder.
+  if (!switches::IsMusHostingViz())
+    return;
+
+  Window window(nullptr);
+  window.Init(ui::LAYER_NOT_DRAWN);
+  window.SetBounds(gfx::Rect(300, 300));
+  window.set_embed_frame_sink_id(viz::FrameSinkId(0, 1));
+
+  // Allocate a new LocalSurfaceId. The ui::Layer should be updated.
+  window.AllocateLocalSurfaceId();
+
+  auto* window_mus = WindowPortMus::Get(&window);
+  viz::LocalSurfaceId local_surface_id = window.GetLocalSurfaceId();
+  viz::SurfaceId primary_surface_id =
+      window_mus->client_surface_embedder()->GetPrimarySurfaceIdForTesting();
+  EXPECT_EQ(local_surface_id, primary_surface_id.local_surface_id());
+}
+
 }  // namespace aura