mus: Implement Window Server Capture

components/mus/ws/window_tree_host_impl.cc

Index: components/mus/ws/window_tree_host_impl.cc
diff --git a/components/mus/ws/window_tree_host_impl.cc b/components/mus/ws/window_tree_host_impl.cc
index 446b32be47d82fe872b576e6ff23e5451481278b..1fa2a97660251b2fb5ca2015dff2441fb0390cc5 100644
--- a/components/mus/ws/window_tree_host_impl.cc
+++ b/components/mus/ws/window_tree_host_impl.cc
@@ -155,6 +155,21 @@ const mojom::ViewportMetrics& WindowTreeHostImpl::GetViewportMetrics() const {
   return display_manager_->GetViewportMetrics();
 }
 
+void WindowTreeHostImpl::SetCapture(ServerWindow* window) {
+  ServerWindow* capture_window = event_dispatcher_.capture_window();

[sky, 2016/01/22 00:55:00]

Early out if window == capture_window?

[jonross, 2016/01/26 18:38:50]

Done.

+  if (capture_window) {
+    WindowTreeImpl* connection =
+        connection_manager_->GetConnection(capture_window->id().connection_id);
+    if (connection)
+      connection->ProcessLostCapture(capture_window);

[jonross, 2016/01/26 18:38:50]

With EventDispatcher now calling EventDispatcherDelegate::OnLostCapture this
would trigger a double notification to the WindowTreeImpl. Removing in favour of
the delegate method.

+  }
+  event_dispatcher_.SetCaptureWindow(window);
+  if (window)
+    display_manager_->SetCapture();
+  else
+    display_manager_->ReleaseCapture();
+}
+
 void WindowTreeHostImpl::SetFocusedWindow(ServerWindow* new_focused_window) {
   ServerWindow* old_focused_window = focus_controller_->GetFocusedWindow();
   if (old_focused_window == new_focused_window)
@@ -385,6 +400,10 @@ void WindowTreeHostImpl::OnEvent(const ui::Event& event) {
   event_dispatcher_.ProcessEvent(std::move(mojo_event));
 }
 
+void WindowTreeHostImpl::OnLostCapture() {
+  SetCapture(nullptr);
+}
+
 void WindowTreeHostImpl::OnDisplayClosed() {
   if (delegate_)
     delegate_->OnDisplayClosed();
@@ -516,6 +535,14 @@ ServerWindow* WindowTreeHostImpl::GetFocusedWindowForEventDispatcher() {
   return GetFocusedWindow();
 }
 
+void WindowTreeHostImpl::OnLostCapture(ServerWindow* window) {
+  DCHECK(window);
+  WindowTreeImpl* connection =
+      connection_manager_->GetConnection(window->id().connection_id);
+  if (connection)
+    connection->ProcessLostCapture(window);
+}
+
 void WindowTreeHostImpl::DispatchInputEventToWindow(ServerWindow* target,
                                                     bool in_nonclient_area,
                                                     mojom::EventPtr event) {