mus: Implement Window Server Capture

components/mus/view_tree_unittest.cc

Index: components/mus/view_tree_unittest.cc
diff --git a/components/mus/view_tree_unittest.cc b/components/mus/view_tree_unittest.cc
index 71380377935a8521cf136a1af52c46844d66ace9..78cae8a7b11bae353c9f5d7539d3e9c404465199 100644
--- a/components/mus/view_tree_unittest.cc
+++ b/components/mus/view_tree_unittest.cc
@@ -61,6 +61,7 @@ class TestViewTreeClient : public mojo::ViewTreeClient {
     tracker_.OnEmbeddedAppDisconnected(view);
   }
   void OnUnembed() override { tracker_.OnUnembed(); }
+  void OnLostCapture(Id view_id) override {}
   void OnViewBoundsChanged(uint32_t view,
                            mojo::RectPtr old_bounds,
                            mojo::RectPtr new_bounds) override {
@@ -217,6 +218,7 @@ class TestDisplayManager : public DisplayManager {
   }
   void SetViewportSize(const gfx::Size& size) override {}
   void SetTitle(const base::string16& title) override {}
+  void SetCapture() override {}
   const mojo::ViewportMetrics& GetViewportMetrics() override {
     return display_metrices_;
   }