Implement window management devtools commands for headless.

headless/lib/browser/headless_browser_impl_aura.cc

 // Copyright 2017 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_browser_impl.h"
 
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
 #include "headless/lib/browser/headless_clipboard.h"
 #include "headless/lib/browser/headless_screen.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window.h"
 #include "ui/base/clipboard/clipboard.h"
 #include "ui/display/screen.h"
 #include "ui/events/devices/device_data_manager.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace headless {
 
 void HeadlessBrowserImpl::PlatformInitialize() {
-  HeadlessScreen* screen = HeadlessScreen::Create(options()->window_size);
+  HeadlessScreen* screen = HeadlessScreen::Create(options()->screen_size);
   display::Screen::SetScreenInstance(screen);
 
   // TODO(eseckler): We shouldn't share clipboard contents across WebContents
   // (or at least BrowserContexts).
   ui::Clipboard::SetClipboardForCurrentThread(
       base::MakeUnique<HeadlessClipboard>());
 }
 
 void HeadlessBrowserImpl::PlatformCreateWindow() {
   DCHECK(aura::Env::GetInstance());
   ui::DeviceDataManager::CreateInstance();
 }
 
 void HeadlessBrowserImpl::PlatformInitializeWebContents(
-    const gfx::Size& initial_size,
+    const gfx::Size& initial_window_size,
+    const gfx::Size& screen_size,
     HeadlessWebContentsImpl* web_contents) {
-  gfx::Rect initial_rect(initial_size);
+  gfx::Rect initial_rect(initial_window_size);
 
   auto window_tree_host =
       base::MakeUnique<HeadlessWindowTreeHost>(initial_rect);
   window_tree_host->InitHost();
   gfx::NativeWindow parent_window = window_tree_host->window();
   parent_window->Show();
   window_tree_host->SetParentWindow(parent_window);
   web_contents->set_window_tree_host(std::move(window_tree_host));
 
   gfx::NativeView contents = web_contents->web_contents()->GetNativeView();
   DCHECK(!parent_window->Contains(contents));
   parent_window->AddChild(contents);
   contents->Show();
   contents->SetBounds(initial_rect);
 
   content::RenderWidgetHostView* host_view =
       web_contents->web_contents()->GetRenderWidgetHostView();
   if (host_view)
-    host_view->SetSize(initial_size);
+    host_view->SetSize(screen_size);

[Eric Seckler, 2017/05/22 19:13:40]

Hm, I don't quite understand screen_size. - Why does the RWHV get the screen
size?

I believe the RWHV should have the same size as the WebContents.

 }
 
 }  // namespace headless