Pass device scale factor from display to ws.

services/ui/ws/test_utils.cc

 // Copyright 2016 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/test_utils.h"
 
 #include <utility>
 
 #include "base/memory/ptr_util.h"
 #include "cc/output/copy_output_request.h"
@@ skipping 23 matching lines @@
       : id_(id),
         is_primary_(is_primary),
         cursor_id_storage_(cursor_id_storage) {
     display_metrics_.bounds = gfx::Rect(0, 0, 400, 300);
     display_metrics_.device_scale_factor = 1.f;
   }
   ~TestPlatformDisplay() override {}
 
   // PlatformDisplay:
   void Init(PlatformDisplayDelegate* delegate) override {
-    // It is necessary to tell the delegate about the ViewportMetrics to make
-    // sure that the DisplayBinding is correctly initialized (and a root-window
-    // is created).
-    delegate->OnViewportMetricsChanged(ViewportMetrics(), display_metrics_);
+    delegate->CreateRootWindow(display_metrics_.bounds.size());
   }
   int64_t GetId() const override { return id_; }
   void SchedulePaint(const ServerWindow* window,
                      const gfx::Rect& bounds) override {}
   void SetViewportSize(const gfx::Size& size) override {}
   void SetTitle(const base::string16& title) override {}
   void SetCapture() override {}
   void ReleaseCapture() override {}
   void SetCursorById(int32_t cursor) override { *cursor_id_storage_ = cursor; }
   display::Display::Rotation GetRotation() override {
@@ skipping 541 matching lines @@
     return nullptr;
   if (!tree->AddWindow(parent_client_id, client_window_id))
     return nullptr;
   *client_id = client_window_id;
   return tree->GetWindowByClientId(client_window_id);
 }
 
 }  // namespace test
 }  // namespace ws
 }  // namespace ui