Makes WindowTreeHost::InitHost() not Show the window

headless/lib/browser/headless_screen.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 "headless/lib/browser/headless_screen.h"
 
 #include <stdint.h>
 
 #include "base/logging.h"
 #include "ui/aura/env.h"
@@ skipping 25 matching lines @@
 
 aura::WindowTreeHost* HeadlessScreen::CreateHostForPrimaryDisplay() {
   DCHECK(!host_);
   host_ = aura::WindowTreeHost::Create(
       gfx::Rect(GetPrimaryDisplay().GetSizeInPixel()));
   // Some tests don't correctly manage window focus/activation states.
   // Makes sure InputMethod is default focused so that IME basics can work.
   host_->GetInputMethod()->OnFocus();
   host_->window()->AddObserver(this);
   host_->InitHost();
+  host_->window()->Show();
   return host_;
 }
 
 void HeadlessScreen::SetDeviceScaleFactor(float device_scale_factor) {
   display::Display display(GetPrimaryDisplay());
   gfx::Rect bounds_in_pixel(display.GetSizeInPixel());
   display.SetScaleAndBounds(device_scale_factor, bounds_in_pixel);
   display_list().UpdateDisplay(display);
 }
 
@@ skipping 94 matching lines @@
 
 HeadlessScreen::HeadlessScreen(const gfx::Rect& screen_bounds)
     : host_(NULL), ui_scale_(1.0f) {
   static int64_t synthesized_display_id = 2000;
   display::Display display(synthesized_display_id++);
   display.SetScaleAndBounds(1.0f, screen_bounds);
   ProcessDisplayChanged(display, true /* is_primary */);
 }
 
 }  // namespace headless