Makes construction of (ash)RemoteWindowTreeHostWin explicit

I need to do this as I need to pass in state to the constructor and I
can't do that with lazy construction. This makes creation a little
saner anyway.

I'm not happy about the static setting the HWND. I'll see if I can
clean that up later.

BUG=none
TEST=none
R=ananta@chromium.org

Review URL: https://codereview.chromium.org/277753002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@270747 0039d316-1c4b-4281-b951-d872f2087c98

31 files changed, 240 insertions, 117 deletions

diff --git a/ash/DEPS b/ash/DEPS
index 86c5214..a92f2d1 100644
--- a/ash/DEPS
+++ b/ash/DEPS
@@ -21,6 +21,9 @@ specific_include_rules = {
   "root_window_controller\.*": [
     "+ash/host"
   ],
+  "shell.cc": [
+    "+ash/host/ash_window_tree_host_init_params.h"
+  ],
   "touch_transformer_controller\.*": [
     "+ash/host"
   ],
diff --git a/ash/accessibility_delegate.h b/ash/accessibility_delegate.h
index 05fb051..7dc2826 100644
--- a/ash/accessibility_delegate.h
+++ b/ash/accessibility_delegate.h
@@ -98,4 +98,4 @@ class ASH_EXPORT AccessibilityDelegate {
 
 }  // namespace ash
 
-#endif  // ASH_ACCESSIBILITYDELEGATE_H_
+#endif  // ASH_ACCESSIBILITY_DELEGATE_H_
diff --git a/ash/ash.gyp b/ash/ash.gyp
index d23db52..0b0f11a 100644
--- a/ash/ash.gyp
+++ b/ash/ash.gyp
@@ -188,6 +188,8 @@
         'host/ash_remote_window_tree_host_win.cc',
         'host/ash_remote_window_tree_host_win.h',
         'host/ash_window_tree_host.h',
+        'host/ash_window_tree_host_init_params.cc',
+        'host/ash_window_tree_host_init_params.h',
         'host/ash_window_tree_host_ozone.cc',
         'host/ash_window_tree_host_win.cc',
         'host/ash_window_tree_host_x11.cc',
@@ -292,6 +294,8 @@
         'shell.h',
         'shell_delegate.h',
         'shell_factory.h',
+        'shell_init_params.cc',
+        'shell_init_params.h',
         'shell_window_ids.h',
         'sticky_keys/sticky_keys_state.h',
         'sticky_keys/sticky_keys_controller.cc',
diff --git a/ash/display/display_controller.cc b/ash/display/display_controller.cc
index 0530533..35ae9d3 100644
--- a/ash/display/display_controller.cc
+++ b/ash/display/display_controller.cc
@@ -16,6 +16,7 @@
 #include "ash/display/root_window_transformers.h"
 #include "ash/display/virtual_keyboard_window_controller.h"
 #include "ash/host/ash_window_tree_host.h"
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/host/root_window_transformer.h"
 #include "ash/root_window_controller.h"
 #include "ash/root_window_settings.h"
@@ -273,11 +274,12 @@ void DisplayController::Shutdown() {
   }
 }
 
-void DisplayController::CreatePrimaryHost() {
+void DisplayController::CreatePrimaryHost(
+    const AshWindowTreeHostInitParams& init_params) {
   const gfx::Display& primary_candidate =
       GetDisplayManager()->GetPrimaryDisplayCandidate();
   primary_display_id = primary_candidate.id();
-  AddWindowTreeHostForDisplay(primary_candidate);
+  AddWindowTreeHostForDisplay(primary_candidate, init_params);
 }
 
 void DisplayController::InitDisplays() {
@@ -288,7 +290,8 @@ void DisplayController::InitDisplays() {
   for (size_t i = 0; i < display_manager->GetNumDisplays(); ++i) {
     const gfx::Display& display = display_manager->GetDisplayAt(i);
     if (primary_display_id != display.id()) {
-      AshWindowTreeHost* ash_host = AddWindowTreeHostForDisplay(display);
+      AshWindowTreeHost* ash_host = AddWindowTreeHostForDisplay(
+          display, AshWindowTreeHostInitParams());
       RootWindowController::CreateForSecondaryDisplay(ash_host);
     }
   }
@@ -570,7 +573,8 @@ void DisplayController::OnDisplayAdded(const gfx::Display& display) {
     if (primary_display_id == gfx::Display::kInvalidDisplayID)
       primary_display_id = display.id();
     DCHECK(!window_tree_hosts_.empty());
-    AshWindowTreeHost* ash_host = AddWindowTreeHostForDisplay(display);
+    AshWindowTreeHost* ash_host = AddWindowTreeHostForDisplay(
+        display, AshWindowTreeHostInitParams());
     RootWindowController::CreateForSecondaryDisplay(ash_host);
   }
 }
@@ -701,12 +705,14 @@ void DisplayController::PostDisplayConfigurationChange() {
 }
 
 AshWindowTreeHost* DisplayController::AddWindowTreeHostForDisplay(
-    const gfx::Display& display) {
+    const gfx::Display& display,
+    const AshWindowTreeHostInitParams& init_params) {
   static int host_count = 0;
   const DisplayInfo& display_info =
       GetDisplayManager()->GetDisplayInfo(display.id());
-  const gfx::Rect& bounds_in_native = display_info.bounds_in_native();
-  AshWindowTreeHost* ash_host = AshWindowTreeHost::Create(bounds_in_native);
+  AshWindowTreeHostInitParams params_with_bounds(init_params);
+  params_with_bounds.initial_bounds = display_info.bounds_in_native();
+  AshWindowTreeHost* ash_host = AshWindowTreeHost::Create(params_with_bounds);
   aura::WindowTreeHost* host = ash_host->AsWindowTreeHost();
 
   host->window()->SetName(base::StringPrintf("RootWindow-%d", host_count++));
diff --git a/ash/display/display_controller.h b/ash/display/display_controller.h
index fb61b84..00c1ac6 100644
--- a/ash/display/display_controller.h
+++ b/ash/display/display_controller.h
@@ -38,6 +38,7 @@ class Insets;
 
 namespace ash {
 class AshWindowTreeHost;
+struct AshWindowTreeHostInitParams;
 class CursorWindowController;
 class DisplayInfo;
 class DisplayManager;
@@ -92,8 +93,9 @@ class ASH_EXPORT DisplayController : public gfx::DisplayObserver,
     return virtual_keyboard_window_controller_.get();
   }
 
-  // Create a WindowTreeHost for the primary display.
-  void CreatePrimaryHost();
+  // Create a WindowTreeHost for the primary display. This replaces
+  // |initial_bounds| in |init_params|.
+  void CreatePrimaryHost(const AshWindowTreeHostInitParams& init_params);
 
   // Initializes all displays.
   void InitDisplays();
@@ -169,7 +171,9 @@ class ASH_EXPORT DisplayController : public gfx::DisplayObserver,
 
   // Creates a WindowTreeHost for |display| and stores it in the
   // |window_tree_hosts_| map.
-  AshWindowTreeHost* AddWindowTreeHostForDisplay(const gfx::Display& display);
+  AshWindowTreeHost* AddWindowTreeHostForDisplay(
+      const gfx::Display& display,
+      const AshWindowTreeHostInitParams& params);
 
   void OnFadeOutForSwapDisplayFinished();
 
diff --git a/ash/display/mirror_window_controller.cc b/ash/display/mirror_window_controller.cc
index 37dcf3b..32d9229 100644
--- a/ash/display/mirror_window_controller.cc
+++ b/ash/display/mirror_window_controller.cc
@@ -17,6 +17,7 @@
 #include "ash/display/display_manager.h"
 #include "ash/display/root_window_transformers.h"
 #include "ash/host/ash_window_tree_host.h"
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/host/root_window_transformer.h"
 #include "ash/root_window_settings.h"
 #include "ash/shell.h"
@@ -81,8 +82,9 @@ MirrorWindowController::~MirrorWindowController() {
 void MirrorWindowController::UpdateWindow(const DisplayInfo& display_info) {
   static int mirror_host_count = 0;
   if (!ash_host_.get()) {
-    const gfx::Rect& bounds_in_native = display_info.bounds_in_native();
-    ash_host_.reset(AshWindowTreeHost::Create(bounds_in_native));
+    AshWindowTreeHostInitParams init_params;
+    init_params.initial_bounds = display_info.bounds_in_native();
+    ash_host_.reset(AshWindowTreeHost::Create(init_params));
     aura::WindowTreeHost* host = ash_host_->AsWindowTreeHost();
     host->window()->SetName(
         base::StringPrintf("MirrorRootWindow-%d", mirror_host_count++));
diff --git a/ash/display/virtual_keyboard_window_controller.cc b/ash/display/virtual_keyboard_window_controller.cc
index 1cec588..b75854a 100644
--- a/ash/display/virtual_keyboard_window_controller.cc
+++ b/ash/display/virtual_keyboard_window_controller.cc
@@ -9,6 +9,7 @@
 #include "ash/display/display_manager.h"
 #include "ash/display/root_window_transformers.h"
 #include "ash/host/ash_window_tree_host.h"
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/host/root_window_transformer.h"
 #include "ash/root_window_controller.h"
 #include "ash/root_window_settings.h"
@@ -42,8 +43,9 @@ void VirtualKeyboardWindowController::UpdateWindow(
     const DisplayInfo& display_info) {
   static int virtual_keyboard_host_count = 0;
   if (!root_window_controller_.get()) {
-    const gfx::Rect& bounds_in_native = display_info.bounds_in_native();
-    AshWindowTreeHost* ash_host = AshWindowTreeHost::Create(bounds_in_native);
+    AshWindowTreeHostInitParams init_params;
+    init_params.initial_bounds = display_info.bounds_in_native();
+    AshWindowTreeHost* ash_host = AshWindowTreeHost::Create(init_params);
     aura::WindowTreeHost* host = ash_host->AsWindowTreeHost();
 
     host->window()->SetName(base::StringPrintf("VirtualKeyboardRootWindow-%d",
diff --git a/ash/host/ash_remote_window_tree_host_win.cc b/ash/host/ash_remote_window_tree_host_win.cc
index ff8c8df..67d3aaa 100644
--- a/ash/host/ash_remote_window_tree_host_win.cc
+++ b/ash/host/ash_remote_window_tree_host_win.cc
@@ -9,32 +9,14 @@
 #include "ui/gfx/transform.h"
 
 namespace ash {
-namespace {
-AshRemoteWindowTreeHostWin* g_instance = NULL;
-}
-
-// static
-void AshRemoteWindowTreeHostWin::Init() {
-  DCHECK(!g_instance);
-  g_instance = new AshRemoteWindowTreeHostWin();
-  aura::RemoteWindowTreeHostWin::SetInstance(g_instance);
-  CHECK_EQ(g_instance, aura::RemoteWindowTreeHostWin::Instance());
-}
-
-// static
-AshRemoteWindowTreeHostWin* AshRemoteWindowTreeHostWin::GetInstance() {
-  if (!g_instance)
-    Init();
-  CHECK_EQ(g_instance, aura::RemoteWindowTreeHostWin::Instance());
-  return g_instance;
-}
 
-AshRemoteWindowTreeHostWin::AshRemoteWindowTreeHostWin()
-    : aura::RemoteWindowTreeHostWin(gfx::Rect()), transformer_helper_(this) {
-  g_instance = this;
+AshRemoteWindowTreeHostWin::AshRemoteWindowTreeHostWin(HWND remote_hwnd)
+    : aura::RemoteWindowTreeHostWin(),
+      transformer_helper_(this) {
+  SetRemoteWindowHandle(remote_hwnd);
 }
 
-AshRemoteWindowTreeHostWin::~AshRemoteWindowTreeHostWin() { g_instance = NULL; }
+AshRemoteWindowTreeHostWin::~AshRemoteWindowTreeHostWin() {}
 
 void AshRemoteWindowTreeHostWin::ToggleFullScreen() {}
 
diff --git a/ash/host/ash_remote_window_tree_host_win.h b/ash/host/ash_remote_window_tree_host_win.h
index 25cdb34..63017f2d 100644
--- a/ash/host/ash_remote_window_tree_host_win.h
+++ b/ash/host/ash_remote_window_tree_host_win.h
@@ -5,6 +5,8 @@
 #ifndef ASH_HOST_REMOTE_WINDOW_TREE_HOST_WIN_H_
 #define ASH_HOST_REMOTE_WINDOW_TREE_HOST_WIN_H_
 
+#include <windows.h>
+
 #include "ash/ash_export.h"
 #include "ash/host/ash_window_tree_host.h"
 #include "ash/host/transformer_helper.h"
@@ -16,17 +18,9 @@ class ASH_EXPORT AshRemoteWindowTreeHostWin
     : public AshWindowTreeHost,
       public aura::RemoteWindowTreeHostWin {
  public:
-  // Creates an instance of AshRemoteWindowTreeHostWin
-  // and sets it to RemoteWindowTreeHostWin::SetInstance.
-  static void Init();
-
-  // Returns the instance created in Init() method above.
-  // This also performs an extra check if the instance is same
-  // one that aura::RemoteWindowTreeHostWin::Instance() returns.
-  static AshRemoteWindowTreeHostWin* GetInstance();
+  explicit AshRemoteWindowTreeHostWin(HWND remote_hwnd);
 
  private:
-  AshRemoteWindowTreeHostWin();
   virtual ~AshRemoteWindowTreeHostWin();
 
   // AshWindowTreeHost:
diff --git a/ash/host/ash_window_tree_host.h b/ash/host/ash_window_tree_host.h
index 00626db..1d1513b 100644
--- a/ash/host/ash_window_tree_host.h
+++ b/ash/host/ash_window_tree_host.h
@@ -19,15 +19,17 @@ class Rect;
 }
 
 namespace ash {
+struct AshWindowTreeHostInitParams;
 class RootWindowTransformer;
 
 class ASH_EXPORT AshWindowTreeHost {
  public:
-  // Creates a new AshWindowTreeHost. The caller owns the returned value.
-  static AshWindowTreeHost* Create(const gfx::Rect& initial_bounds);
-
   virtual ~AshWindowTreeHost() {}
 
+  // Creates a new AshWindowTreeHost. The caller owns the returned value.
+  static AshWindowTreeHost* Create(
+      const AshWindowTreeHostInitParams& init_params);
+
   // Toggles the host's full screen state.
   virtual void ToggleFullScreen() = 0;
 
diff --git a/ash/host/ash_window_tree_host_init_params.cc b/ash/host/ash_window_tree_host_init_params.cc
new file mode 100644
index 0000000..55d15c0
--- /dev/null
+++ b/ash/host/ash_window_tree_host_init_params.cc
@@ -0,0 +1,19 @@
+// Copyright 2014 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 "ash/host/ash_window_tree_host_init_params.h"
+
+namespace ash {
+
+#if defined(OS_WIN)
+AshWindowTreeHostInitParams::AshWindowTreeHostInitParams() : remote_hwnd(NULL) {
+#else
+AshWindowTreeHostInitParams::AshWindowTreeHostInitParams() {
+#endif
+}
+
+AshWindowTreeHostInitParams::~AshWindowTreeHostInitParams() {
+}
+
+}  // namespace ash
diff --git a/ash/host/ash_window_tree_host_init_params.h b/ash/host/ash_window_tree_host_init_params.h
new file mode 100644
index 0000000..d9bb7de
--- /dev/null
+++ b/ash/host/ash_window_tree_host_init_params.h
@@ -0,0 +1,32 @@
+// Copyright 2014 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.
+
+#ifndef ASH_HOST_WINDOW_TREE_HOST_INIT_PARAMS_H_
+#define ASH_HOST_WINDOW_TREE_HOST_INIT_PARAMS_H_
+
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include <windows.h>
+#endif
+
+#include "ash/ash_export.h"
+#include "ui/gfx/geometry/rect.h"
+
+namespace ash {
+
+struct ASH_EXPORT AshWindowTreeHostInitParams {
+  AshWindowTreeHostInitParams();
+  ~AshWindowTreeHostInitParams();
+
+  gfx::Rect initial_bounds;
+
+#if defined(OS_WIN)
+  HWND remote_hwnd;
+#endif
+};
+
+}  // namespace ash
+
+#endif  // ASH_HOST_WINDOW_TREE_HOST_INIT_PARAMS_H_
diff --git a/ash/host/ash_window_tree_host_ozone.cc b/ash/host/ash_window_tree_host_ozone.cc
index 8fe2ba5..5bbf06b 100644
--- a/ash/host/ash_window_tree_host_ozone.cc
+++ b/ash/host/ash_window_tree_host_ozone.cc
@@ -4,6 +4,7 @@
 
 #include "ash/host/ash_window_tree_host.h"
 
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/host/root_window_transformer.h"
 #include "ash/host/transformer_helper.h"
 #include "base/command_line.h"
@@ -88,8 +89,9 @@ void AshWindowTreeHostOzone::UpdateRootWindowSize(const gfx::Size& host_size) {
 
 }  // namespace
 
-AshWindowTreeHost* AshWindowTreeHost::Create(const gfx::Rect& initial_bounds) {
-  return new AshWindowTreeHostOzone(initial_bounds);
+AshWindowTreeHost* AshWindowTreeHost::Create(
+    const AshWindowTreeHostInitParams& init_params) {
+  return new AshWindowTreeHostOzone(intial_params.initial_bounds);
 }
 
 }  // namespace ash
diff --git a/ash/host/ash_window_tree_host_win.cc b/ash/host/ash_window_tree_host_win.cc
index 642501a..30f98f6 100644
--- a/ash/host/ash_window_tree_host_win.cc
+++ b/ash/host/ash_window_tree_host_win.cc
@@ -7,6 +7,7 @@
 #include "ash/ash_export.h"
 #include "ash/ash_switches.h"
 #include "ash/host/ash_remote_window_tree_host_win.h"
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/host/root_window_transformer.h"
 #include "ash/host/transformer_helper.h"
 #include "base/command_line.h"
@@ -110,13 +111,14 @@ class ASH_EXPORT AshWindowTreeHostWin : public AshWindowTreeHost,
 
 }  // namespace
 
-AshWindowTreeHost* AshWindowTreeHost::Create(const gfx::Rect& initial_bounds) {
+AshWindowTreeHost* AshWindowTreeHost::Create(
+    const AshWindowTreeHostInitParams& init_params) {
   if (base::win::GetVersion() >= base::win::VERSION_WIN7 &&
       !CommandLine::ForCurrentProcess()->HasSwitch(
           ash::switches::kForceAshToDesktop))
-    return AshRemoteWindowTreeHostWin::GetInstance();
+    return new AshRemoteWindowTreeHostWin(init_params.remote_hwnd);
 
-  return new AshWindowTreeHostWin(initial_bounds);
+  return new AshWindowTreeHostWin(init_params.initial_bounds);
 }
 
 }  // namespace ash
diff --git a/ash/host/ash_window_tree_host_x11.cc b/ash/host/ash_window_tree_host_x11.cc
index b9f33f1..a050a34 100644
--- a/ash/host/ash_window_tree_host_x11.cc
+++ b/ash/host/ash_window_tree_host_x11.cc
@@ -12,6 +12,7 @@
 #include <string>
 #include <vector>
 
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/host/root_window_transformer.h"
 #include "base/basictypes.h"
 #include "base/sys_info.h"
@@ -281,8 +282,9 @@ void AshWindowTreeHostX11::SetCrOSTapPaused(bool state) {
   }
 }
 
-AshWindowTreeHost* AshWindowTreeHost::Create(const gfx::Rect& initial_bounds) {
-  return new AshWindowTreeHostX11(initial_bounds);
+AshWindowTreeHost* AshWindowTreeHost::Create(
+    const AshWindowTreeHostInitParams& init_params) {
+  return new AshWindowTreeHostX11(init_params.initial_bounds);
 }
 
 }  // namespace ash
diff --git a/ash/shell.cc b/ash/shell.cc
index 7c0773f..d2322d8 100644
--- a/ash/shell.cc
+++ b/ash/shell.cc
@@ -30,6 +30,7 @@
 #include "ash/frame/custom_frame_view_ash.h"
 #include "ash/gpu_support.h"
 #include "ash/high_contrast/high_contrast_controller.h"
+#include "ash/host/ash_window_tree_host_init_params.h"
 #include "ash/keyboard_uma_event_filter.h"
 #include "ash/magnifier/magnification_controller.h"
 #include "ash/magnifier/partial_magnification_controller.h"
@@ -47,6 +48,7 @@
 #include "ash/shelf/shelf_window_watcher.h"
 #include "ash/shell_delegate.h"
 #include "ash/shell_factory.h"
+#include "ash/shell_init_params.h"
 #include "ash/shell_window_ids.h"
 #include "ash/system/locale/locale_notification_controller.h"
 #include "ash/system/status_area_widget.h"
@@ -163,6 +165,15 @@ class AshVisibilityController : public ::wm::VisibilityController {
   DISALLOW_COPY_AND_ASSIGN(AshVisibilityController);
 };
 
+AshWindowTreeHostInitParams ShellInitParamsToAshWindowTreeHostInitParams(
+    const ShellInitParams& shell_init_params) {
+  AshWindowTreeHostInitParams ash_init_params;
+#if defined(OS_WIN)
+  ash_init_params.remote_hwnd = shell_init_params.remote_hwnd;
+#endif
+  return ash_init_params;
+}
+
 }  // namespace
 
 // static
@@ -174,10 +185,10 @@ bool Shell::initially_hide_cursor_ = false;
 // Shell, public:
 
 // static
-Shell* Shell::CreateInstance(ShellDelegate* delegate) {
+Shell* Shell::CreateInstance(const ShellInitParams& init_params) {
   CHECK(!instance_);
-  instance_ = new Shell(delegate);
-  instance_->Init();
+  instance_ = new Shell(init_params.delegate);
+  instance_->Init(init_params);
   return instance_;
 }
 
@@ -797,7 +808,7 @@ Shell::~Shell() {
   instance_ = NULL;
 }
 
-void Shell::Init() {
+void Shell::Init(const ShellInitParams& init_params) {
   delegate_->PreInit();
   if (keyboard::IsKeyboardUsabilityExperimentEnabled()) {
     display_manager_->SetSecondDisplayMode(DisplayManager::VIRTUAL_KEYBOARD);
@@ -858,7 +869,8 @@ void Shell::Init() {
   screen_position_controller_.reset(new ScreenPositionController);
 
   display_controller_->Start();
-  display_controller_->CreatePrimaryHost();
+  display_controller_->CreatePrimaryHost(
+      ShellInitParamsToAshWindowTreeHostInitParams(init_params));
   aura::Window* root_window = display_controller_->GetPrimaryRootWindow();
   target_root_window_ = root_window;
 
diff --git a/ash/shell.h b/ash/shell.h
index df906c2..e889131 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -126,6 +126,7 @@ class ShelfItemDelegateManager;
 class ShelfModel;
 class ShelfWindowWatcher;
 class ShellDelegate;
+struct ShellInitParams;
 class ShellObserver;
 class SlowAnimationEventFilter;
 class StatusAreaWidget;
@@ -174,7 +175,7 @@ class ASH_EXPORT Shell : public SystemModalContainerEventFilterDelegate,
   // A shell must be explicitly created so that it can call |Init()| with the
   // delegate set. |delegate| can be NULL (if not required for initialization).
   // Takes ownership of |delegate|.
-  static Shell* CreateInstance(ShellDelegate* delegate);
+  static Shell* CreateInstance(const ShellInitParams& init_params);
 
   // Should never be called before |CreateInstance()|.
   static Shell* GetInstance();
@@ -581,7 +582,7 @@ class ASH_EXPORT Shell : public SystemModalContainerEventFilterDelegate,
   explicit Shell(ShellDelegate* delegate);
   virtual ~Shell();
 
-  void Init();
+  void Init(const ShellInitParams& init_params);
 
   // Initializes virtual keyboard controller.
   void InitKeyboard();
diff --git a/ash/shell/content_client/shell_browser_main_parts.cc b/ash/shell/content_client/shell_browser_main_parts.cc
index 7223920..8c2a37a 100644
--- a/ash/shell/content_client/shell_browser_main_parts.cc
+++ b/ash/shell/content_client/shell_browser_main_parts.cc
@@ -9,6 +9,7 @@
 #include "ash/shell.h"
 #include "ash/shell/shell_delegate_impl.h"
 #include "ash/shell/window_watcher.h"
+#include "ash/shell_init_params.h"
 #include "ash/system/user/login_status.h"
 #include "base/bind.h"
 #include "base/command_line.h"
@@ -121,7 +122,9 @@ void ShellBrowserMainParts::PreMainMessageLoopRun() {
   chromeos::CrasAudioHandler::InitializeForTesting();
 #endif
 
-  ash::Shell::CreateInstance(delegate_);
+  ash::ShellInitParams init_params;
+  init_params.delegate = delegate_;
+  ash::Shell::CreateInstance(init_params);
   delegate_->set_browser_context(browser_context_.get());
   ash::Shell::GetInstance()->CreateShelf();
   ash::Shell::GetInstance()->UpdateAfterLoginStatusChange(
diff --git a/ash/shell/window_watcher_unittest.cc b/ash/shell/window_watcher_unittest.cc
index 90ed407..dd5ea40 100644
--- a/ash/shell/window_watcher_unittest.cc
+++ b/ash/shell/window_watcher_unittest.cc
@@ -5,8 +5,9 @@
 #include "ash/shell/window_watcher.h"
 
 #include "ash/shell.h"
-#include "ash/shell_delegate.h"
 #include "ash/shell/shell_delegate_impl.h"
+#include "ash/shell_delegate.h"
+#include "ash/shell_init_params.h"
 #include "ash/system/user/login_status.h"
 #include "ash/test/ash_test_base.h"
 #include "ui/aura/window_tree_host.h"
@@ -23,7 +24,9 @@ TEST_F(WindowWatcherTest, ShellDeleteInstance) {
   Shell::DeleteInstance();
 
   shell::ShellDelegateImpl* delegate = new ash::shell::ShellDelegateImpl;
-  Shell::CreateInstance(delegate);
+  ash::ShellInitParams init_params;
+  init_params.delegate = delegate;
+  Shell::CreateInstance(init_params);
   Shell::GetPrimaryRootWindow()->GetHost()->Show();
   Shell::GetInstance()->CreateShelf();
   Shell::GetInstance()->UpdateAfterLoginStatusChange(
diff --git a/ash/shell_init_params.cc b/ash/shell_init_params.cc
new file mode 100644
index 0000000..87e5be8
--- /dev/null
+++ b/ash/shell_init_params.cc
@@ -0,0 +1,19 @@
+// Copyright 2014 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 "ash/shell_init_params.h"
+
+#include "ash/shell_delegate.h"
+
+namespace ash {
+
+#if defined(OS_WIN)
+ShellInitParams::ShellInitParams() : delegate(NULL), remote_hwnd(NULL) {}
+#else
+ShellInitParams::ShellInitParams() : delegate(NULL) {}
+#endif
+
+ShellInitParams::~ShellInitParams() {}
+
+}  // namespace ash
diff --git a/ash/shell_init_params.h b/ash/shell_init_params.h
new file mode 100644
index 0000000..52b894e
--- /dev/null
+++ b/ash/shell_init_params.h
@@ -0,0 +1,33 @@
+// Copyright 2014 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.
+
+#ifndef ASH_SHELL_INIT_PARAMS_H_
+#define ASH_SHELL_INIT_PARAMS_H_
+
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
+#include <windows.h>
+#endif
+
+#include "ash/ash_export.h"
+
+namespace ash {
+
+class ShellDelegate;
+
+struct ASH_EXPORT ShellInitParams {
+  ShellInitParams();
+  ~ShellInitParams();
+
+  ShellDelegate* delegate;
+
+#if defined(OS_WIN)
+  HWND remote_hwnd;
+#endif
+};
+
+}  // namespace ash
+
+#endif  // ASH_SHELL_INIT_PARAMS_H_
diff --git a/ash/test/ash_test_helper.cc b/ash/test/ash_test_helper.cc
index a59019b..3dd9455 100644
--- a/ash/test/ash_test_helper.cc
+++ b/ash/test/ash_test_helper.cc
@@ -7,6 +7,7 @@
 #include "ash/accelerators/accelerator_controller.h"
 #include "ash/ash_switches.h"
 #include "ash/shell.h"
+#include "ash/shell_init_params.h"
 #include "ash/test/ash_test_views_delegate.h"
 #include "ash/test/display_manager_test_api.h"
 #include "ash/test/shell_test_api.h"
@@ -84,7 +85,9 @@ void AshTestHelper::SetUp(bool start_session) {
   // created in AshTestBase tests.
   chromeos::CrasAudioHandler::InitializeForTesting();
 #endif
-  ash::Shell::CreateInstance(test_shell_delegate_);
+  ShellInitParams init_params;
+  init_params.delegate = test_shell_delegate_;
+  ash::Shell::CreateInstance(init_params);
   aura::test::EnvTestHelper(aura::Env::GetInstance()).SetInputStateLookup(
       scoped_ptr<aura::InputStateLookup>());
 
diff --git a/ash/test/test_metro_viewer_process_host.cc b/ash/test/test_metro_viewer_process_host.cc
index 5dd448c..85df3e2 100644
--- a/ash/test/test_metro_viewer_process_host.cc
+++ b/ash/test/test_metro_viewer_process_host.cc
@@ -8,13 +8,15 @@
 
 #include "base/logging.h"
 #include "ui/aura/remote_window_tree_host_win.h"
+#include "ui/gfx/win/dpi.h"
 
 namespace ash {
 namespace test {
 
 TestMetroViewerProcessHost::TestMetroViewerProcessHost(
     base::SingleThreadTaskRunner* ipc_task_runner)
-        : MetroViewerProcessHost(ipc_task_runner), closed_unexpectedly_(false) {
+    : MetroViewerProcessHost(ipc_task_runner),
+      closed_unexpectedly_(false) {
 }
 
 TestMetroViewerProcessHost::~TestMetroViewerProcessHost() {
@@ -30,8 +32,8 @@ void TestMetroViewerProcessHost::OnSetTargetSurface(
     float device_scale) {
   DLOG(INFO) << __FUNCTION__ << ", target_surface = " << target_surface;
   HWND hwnd = reinterpret_cast<HWND>(target_surface);
-  aura::RemoteWindowTreeHostWin::Instance()->
-      InitializeRemoteWindowAndScaleFactor(hwnd, device_scale);
+  gfx::InitDeviceScaleFactor(device_scale);
+  aura::RemoteWindowTreeHostWin::Instance()->SetRemoteWindowHandle(hwnd);
   aura::RemoteWindowTreeHostWin::Instance()->Connected(this);
 }
 
diff --git a/chrome/browser/metro_viewer/chrome_metro_viewer_process_host_aurawin.cc b/chrome/browser/metro_viewer/chrome_metro_viewer_process_host_aurawin.cc
index 374f300..277a5aa 100644
--- a/chrome/browser/metro_viewer/chrome_metro_viewer_process_host_aurawin.cc
+++ b/chrome/browser/metro_viewer/chrome_metro_viewer_process_host_aurawin.cc
@@ -120,14 +120,10 @@ void ChromeMetroViewerProcessHost::OnSetTargetSurface(
     float device_scale) {
   HWND hwnd = reinterpret_cast<HWND>(target_surface);
 
-  // Make hwnd available as early as possible for proper InputMethod
-  // initialization.
-  ash::AshRemoteWindowTreeHostWin::Init();
-  aura::RemoteWindowTreeHostWin::Instance()->
-      InitializeRemoteWindowAndScaleFactor(hwnd, device_scale);
-
-  // Now start the Ash shell environment.
-  chrome::OpenAsh();
+  gfx::InitDeviceScaleFactor(device_scale);
+  chrome::OpenAsh(hwnd);
+  DCHECK(aura::RemoteWindowTreeHostWin::Instance());
+  DCHECK_EQ(hwnd, aura::RemoteWindowTreeHostWin::Instance()->remote_window());
   ash::Shell::GetInstance()->CreateShelf();
   ash::Shell::GetInstance()->ShowShelf();
 
diff --git a/chrome/browser/ui/ash/ash_init.cc b/chrome/browser/ui/ash/ash_init.cc
index c3a8b51..06ab94e 100644
--- a/chrome/browser/ui/ash/ash_init.cc
+++ b/chrome/browser/ui/ash/ash_init.cc
@@ -11,6 +11,7 @@
 #include "ash/magnifier/magnification_controller.h"
 #include "ash/magnifier/partial_magnification_controller.h"
 #include "ash/shell.h"
+#include "ash/shell_init_params.h"
 #include "base/command_line.h"
 #include "chrome/browser/browser_shutdown.h"
 #include "chrome/browser/lifetime/application_lifetime.h"
@@ -42,7 +43,7 @@ bool ShouldOpenAshOnStartup() {
   return CommandLine::ForCurrentProcess()->HasSwitch(switches::kOpenAsh);
 }
 
-void OpenAsh() {
+void OpenAsh(gfx::AcceleratedWidget remote_window) {
 #if defined(OS_CHROMEOS)
 #if defined(USE_X11)
   if (base::SysInfo::IsRunningOnChromeOS()) {
@@ -58,8 +59,14 @@ void OpenAsh() {
     ash::Shell::set_initially_hide_cursor(true);
 #endif
 
+  ash::ShellInitParams shell_init_params;
   // Shell takes ownership of ChromeShellDelegate.
-  ash::Shell* shell = ash::Shell::CreateInstance(new ChromeShellDelegate);
+  shell_init_params.delegate = new ChromeShellDelegate;
+#if defined(OS_WIN)
+  shell_init_params.remote_hwnd = remote_window;
+#endif
+
+  ash::Shell* shell = ash::Shell::CreateInstance(shell_init_params);
   shell->accelerator_controller()->SetScreenshotDelegate(
       scoped_ptr<ash::ScreenshotDelegate>(new ScreenshotTaker).Pass());
   // TODO(flackr): Investigate exposing a blocking pool task runner to chromeos.
diff --git a/chrome/browser/ui/ash/ash_init.h b/chrome/browser/ui/ash/ash_init.h
index 6ed1a0f..b1141bd 100644
--- a/chrome/browser/ui/ash/ash_init.h
+++ b/chrome/browser/ui/ash/ash_init.h
@@ -5,13 +5,16 @@
 #ifndef CHROME_BROWSER_UI_ASH_ASH_INIT_H_
 #define CHROME_BROWSER_UI_ASH_ASH_INIT_H_
 
+#include "ui/gfx/native_widget_types.h"
+
 namespace chrome {
 
 // Returns true if Ash should be run at startup.
 bool ShouldOpenAshOnStartup();
 
-// Creates the Ash Shell and opens the Ash window.
-void OpenAsh();
+// Creates the Ash Shell and opens the Ash window. |remote_window| is only used
+// on windows. It provides the HWND to the remote window.
+void OpenAsh(gfx::AcceleratedWidget remote_window);
 
 // Closes the Ash window and destroys the Ash Shell.
 void CloseAsh();
diff --git a/chrome/browser/ui/ash/ash_util.cc b/chrome/browser/ui/ash/ash_util.cc
index 0b3bdcc..f2670de 100644
--- a/chrome/browser/ui/ash/ash_util.cc
+++ b/chrome/browser/ui/ash/ash_util.cc
@@ -41,7 +41,7 @@ void ToggleAshDesktop() {
     return;
 
   if (!ash::Shell::HasInstance())
-    OpenAsh();
+    OpenAsh(gfx::kNullAcceleratedWidget);
   else
     CloseAsh();
 }
diff --git a/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc b/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
index 6b858b7..f1c3b62 100644
--- a/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
+++ b/chrome/browser/ui/views/ash/chrome_browser_main_extra_parts_ash.cc
@@ -67,7 +67,7 @@ ChromeBrowserMainExtraPartsAsh::~ChromeBrowserMainExtraPartsAsh() {
 
 void ChromeBrowserMainExtraPartsAsh::PreProfileInit() {
   if (chrome::ShouldOpenAshOnStartup()) {
-    chrome::OpenAsh();
+    chrome::OpenAsh(gfx::kNullAcceleratedWidget);
   } else {
 #if !defined(OS_CHROMEOS)
     gfx::Screen::SetScreenTypeDelegate(new ScreenTypeDelegateWin);
diff --git a/chrome/test/base/view_event_test_base.cc b/chrome/test/base/view_event_test_base.cc
index bdba76a..2d64c5d 100644
--- a/chrome/test/base/view_event_test_base.cc
+++ b/chrome/test/base/view_event_test_base.cc
@@ -29,6 +29,7 @@
 
 #if defined(USE_ASH)
 #include "ash/shell.h"
+#include "ash/shell_init_params.h"
 #include "ash/test/test_session_state_delegate.h"
 #include "ash/test/test_shell_delegate.h"
 #endif
@@ -128,7 +129,9 @@ void ViewEventTestBase::SetUp() {
 #endif  // OS_CHROMEOS
   ash::test::TestShellDelegate* shell_delegate =
       new ash::test::TestShellDelegate();
-  ash::Shell::CreateInstance(shell_delegate);
+  ash::ShellInitParams init_params;
+  init_params.delegate = shell_delegate;
+  ash::Shell::CreateInstance(init_params);
   shell_delegate->test_session_state_delegate()
       ->SetActiveUserSessionStarted(true);
   context = ash::Shell::GetPrimaryRootWindow();
diff --git a/ui/aura/remote_window_tree_host_win.cc b/ui/aura/remote_window_tree_host_win.cc
index 31aa551..2dbc0e7 100644
--- a/ui/aura/remote_window_tree_host_win.cc
+++ b/ui/aura/remote_window_tree_host_win.cc
@@ -151,23 +151,17 @@ RemoteWindowTreeHostWin* g_instance = NULL;
 
 // static
 RemoteWindowTreeHostWin* RemoteWindowTreeHostWin::Instance() {
-  if (!g_instance)
-    g_instance = new RemoteWindowTreeHostWin(gfx::Rect());
   return g_instance;
 }
 
-// static
-void RemoteWindowTreeHostWin::SetInstance(RemoteWindowTreeHostWin* instance) {
-  CHECK(!g_instance);
-  g_instance = instance;
-}
-
-RemoteWindowTreeHostWin::RemoteWindowTreeHostWin(const gfx::Rect& bounds)
+RemoteWindowTreeHostWin::RemoteWindowTreeHostWin()
     : remote_window_(NULL),
       host_(NULL),
       ignore_mouse_moves_until_set_cursor_ack_(false),
       event_flags_(0),
       window_size_(aura::WindowTreeHost::GetNativeScreenSize()) {
+  CHECK(!g_instance);
+  g_instance = this;
   prop_.reset(new ui::ViewProp(NULL, kWindowTreeHostWinKey, this));
   CreateCompositor(GetAcceleratedWidget());
 }
@@ -175,6 +169,7 @@ RemoteWindowTreeHostWin::RemoteWindowTreeHostWin(const gfx::Rect& bounds)
 RemoteWindowTreeHostWin::~RemoteWindowTreeHostWin() {
   DestroyCompositor();
   DestroyDispatcher();
+  DCHECK_EQ(g_instance, this);
   g_instance = NULL;
 }
 
@@ -183,13 +178,8 @@ bool RemoteWindowTreeHostWin::IsValid() {
   return Instance()->remote_window_ != NULL;
 }
 
-void RemoteWindowTreeHostWin::InitializeRemoteWindowAndScaleFactor(
-    HWND remote_window,
-    float device_scale) {
+void RemoteWindowTreeHostWin::SetRemoteWindowHandle(HWND remote_window) {
   remote_window_ = remote_window;
-  gfx::InitDeviceScaleFactor(device_scale);
-  // Do not create compositor here, but in Connected() below.
-  // See http://crbug.com/330179 and http://crbug.com/334380.
 }
 
 void RemoteWindowTreeHostWin::Connected(IPC::Sender* host) {
diff --git a/ui/aura/remote_window_tree_host_win.h b/ui/aura/remote_window_tree_host_win.h
index 0ff913e..9cc7439 100644
--- a/ui/aura/remote_window_tree_host_win.h
+++ b/ui/aura/remote_window_tree_host_win.h
@@ -106,27 +106,19 @@ class AURA_EXPORT RemoteWindowTreeHostWin
       public ui::EventSource,
       public ui::internal::RemoteInputMethodDelegateWin {
  public:
-  // Returns the only RemoteWindowTreeHostWin, if this is the first time
-  // this function is called and the instance have never set by SetInstance,
-  // it will call Create() wiht empty bounds.
+  // Returns the current RemoteWindowTreeHostWin. This does *not* create a
+  // RemoteWindowTreeHostWin.
   static RemoteWindowTreeHostWin* Instance();
 
-  // Manually sets the instance to be used as a return value of |Instance()|
-  // method above. This should not be called if the instance has already
-  // been set or created, and doing so will result in CHECK failure.
-  static void SetInstance(RemoteWindowTreeHostWin* instance);
-
   // Returns true if there is a RemoteWindowTreeHostWin and it has a valid
   // HWND. A return value of false typically indicates we're not in metro mode.
   static bool IsValid();
 
-  // Sets the handle to the remote window and the scale factor. The
-  // |remote_window| is the actual window owned by the viewer process. Call
-  // this before Connected() for some customers like input method
-  // initialization which needs the handle.
-  // |device_scale| indicates the Windows 8 dpi scale.
-  void InitializeRemoteWindowAndScaleFactor(HWND remote_window,
-                                            float device_scale);
+  // Sets the handle to the remote window. The |remote_window| is the actual
+  // window owned by the viewer process. Call this before Connected() for some
+  // customers like input method initialization which needs the handle.
+  void SetRemoteWindowHandle(HWND remote_window);
+  HWND remote_window() { return remote_window_; }
 
   // The |host| can be used when we need to send a message to it.
   void Connected(IPC::Sender* host);
@@ -180,7 +172,7 @@ class AURA_EXPORT RemoteWindowTreeHostWin
   bool IsForegroundWindow();
 
  protected:
-  explicit RemoteWindowTreeHostWin(const gfx::Rect& bounds);
+  RemoteWindowTreeHostWin();
   virtual ~RemoteWindowTreeHostWin();
 
  private: