Pass device scale factor from display to ws.

services/ui/ws/display.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 "services/ui/ws/display.h"
 
 #include <set>
 #include <utility>
 #include <vector>
 
@@ skipping 267 matching lines @@
   display_root->window_manager_state_ = window_manager_state;
   const bool is_active =
       factory->user_id() == window_server_->user_id_tracker()->active_id();
   display_root->root()->SetVisible(is_active);
   window_manager_state->window_tree()->AddRootForWindowManager(
       display_root->root());
   window_manager_state->AddWindowManagerDisplayRoot(
       std::move(display_root_ptr));
 }
 
+void Display::CreateRootWindow(const gfx::Size& size) {
+  DCHECK(!root_);
+
+  root_.reset(window_server_->CreateServerWindow(
+      display_manager()->GetAndAdvanceNextRootId(),
+      ServerWindow::Properties()));
+  root_->SetBounds(gfx::Rect(size));
+  root_->SetVisible(true);
+  focus_controller_.reset(new FocusController(this, root_.get()));
+  focus_controller_->AddObserver(this);
+  InitWindowManagerDisplayRootsIfNecessary();
+}
+
 ServerWindow* Display::GetRootWindow() {
   return root_.get();
 }
 
 bool Display::IsInHighContrastMode() {
   return window_server_->IsActiveUserInHighContrastMode();
 }
 
 void Display::OnEvent(const ui::Event& event) {
   WindowManagerDisplayRoot* display_root = GetActiveWindowManagerDisplayRoot();
   if (display_root)
     display_root->window_manager_state()->ProcessEvent(event);
   window_server_
       ->GetUserActivityMonitorForUser(
           window_server_->user_id_tracker()->active_id())
       ->OnUserActivity();
 }
 
 void Display::OnNativeCaptureLost() {
   WindowManagerDisplayRoot* display_root = GetActiveWindowManagerDisplayRoot();
   if (display_root)
     display_root->window_manager_state()->SetCapture(nullptr, kInvalidClientId);
 }
 
 void Display::OnViewportMetricsChanged(const ViewportMetrics& old_metrics,
                                        const ViewportMetrics& new_metrics) {
+  if (!root_)
+    return;
+
   gfx::Rect new_bounds(new_metrics.bounds.size());
-  if (!root_) {
-    root_.reset(window_server_->CreateServerWindow(
-        display_manager()->GetAndAdvanceNextRootId(),
-        ServerWindow::Properties()));
-    root_->SetBounds(new_bounds);
-    root_->SetVisible(true);
-    focus_controller_.reset(new FocusController(this, root_.get()));
-    focus_controller_->AddObserver(this);
-    InitWindowManagerDisplayRootsIfNecessary();
-  } else {
-    root_->SetBounds(new_bounds);
-    for (auto& pair : window_manager_display_root_map_)
-      pair.second->root()->SetBounds(new_bounds);
-  }
-  if (init_called_)
-    display_manager()->OnDisplayUpdate(this);
+  root_->SetBounds(new_bounds);
+  for (auto& pair : window_manager_display_root_map_)
+    pair.second->root()->SetBounds(new_bounds);
+
+  display_manager()->OnDisplayUpdate(this);

[sky, 2016/09/22 21:42:06]

Why is it safe to not check init_called?

[kylechar, 2016/09/23 13:22:32]

OnDisplayUpdate() was getting called during initialization when the root
ServerWindow was created but before the ash WindowTreeClient was done updating.

The root ServerWindow creation happens in CreateRootWindow() now so that isn't a
problem.

 }
 
 void Display::OnCompositorFrameDrawn() {
   std::set<ServerWindow*> windows;
   windows.swap(windows_needing_frame_destruction_);
   for (ServerWindow* window : windows) {
     window->RemoveObserver(this);
     window->DestroySurfacesScheduledForDestruction();
   }
 }
@@ skipping 84 matching lines @@
 }
 
 void Display::OnWindowManagerWindowTreeFactoryReady(
     WindowManagerWindowTreeFactory* factory) {
   if (!binding_)
     CreateWindowManagerDisplayRootFromFactory(factory);
 }
 
 }  // namespace ws
 }  // namespace ui