Introdcue AshWindowTreeHost and move ash/chrome specific code in WTH to ash.

ash/host/ash_window_tree_host_win.cc

Index: ash/host/ash_window_tree_host_win.cc
diff --git a/ash/host/ash_window_tree_host_win.cc b/ash/host/ash_window_tree_host_win.cc
new file mode 100644
index 0000000000000000000000000000000000000000..5ea0f4a1ae5e5b0ab062c9f2a8217d9899952996
--- /dev/null
+++ b/ash/host/ash_window_tree_host_win.cc
@@ -0,0 +1,119 @@
+// 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.h"
+
+#include "ash/ash_export.h"
+#include "ash/ash_switches.h"
+#include "ash/host/ash_remote_window_tree_host_win.h"
+#include "ash/host/root_window_transformer.h"
+#include "ash/host/transformer_helper.h"
+#include "base/command_line.h"
+#include "base/win/windows_version.h"
+#include "ui/aura/window_tree_host_win.h"
+#include "ui/gfx/geometry/insets.h"
+#include "ui/gfx/transform.h"
+
+namespace ash {
+namespace {
+
+class ASH_EXPORT AshWindowTreeHostWin : public AshWindowTreeHost,
+                                        public aura::WindowTreeHostWin {
+ public:
+  explicit AshWindowTreeHostWin(const gfx::Rect& initial_bounds)
+      : aura::WindowTreeHostWin(initial_bounds),
+        fullscreen_(false),
+        saved_window_style_(0),
+        saved_window_ex_style_(0),
+        transformer_helper_(this) {}
+  virtual ~AshWindowTreeHostWin() {}
+
+ private:
+  // AshWindowTreeHost:
+  virtual void ToggleFullScreen() OVERRIDE {
+    gfx::Rect target_rect;
+    if (!fullscreen_) {
+      fullscreen_ = true;
+      saved_window_style_ = GetWindowLong(hwnd(), GWL_STYLE);
+      saved_window_ex_style_ = GetWindowLong(hwnd(), GWL_EXSTYLE);
+      GetWindowRect(hwnd(), &saved_window_rect_);
+      SetWindowLong(hwnd(),
+                    GWL_STYLE,
+                    saved_window_style_ & ~(WS_CAPTION | WS_THICKFRAME));
+      SetWindowLong(
+          hwnd(),
+          GWL_EXSTYLE,
+          saved_window_ex_style_ & ~(WS_EX_DLGMODALFRAME | WS_EX_WINDOWEDGE |
+                                     WS_EX_CLIENTEDGE | WS_EX_STATICEDGE));
+
+      MONITORINFO mi;
+      mi.cbSize = sizeof(mi);
+      GetMonitorInfo(MonitorFromWindow(hwnd(), MONITOR_DEFAULTTONEAREST), &mi);
+      target_rect = gfx::Rect(mi.rcMonitor);
+    } else {
+      fullscreen_ = false;
+      SetWindowLong(hwnd(), GWL_STYLE, saved_window_style_);
+      SetWindowLong(hwnd(), GWL_EXSTYLE, saved_window_ex_style_);
+      target_rect = gfx::Rect(saved_window_rect_);
+    }
+    SetWindowPos(hwnd(),
+                 NULL,
+                 target_rect.x(),
+                 target_rect.y(),
+                 target_rect.width(),
+                 target_rect.height(),
+                 SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED);
+  }
+  virtual bool ConfineCursorToRootWindow() OVERRIDE { return false; }
+  virtual void UnConfineCursor() OVERRIDE { NOTIMPLEMENTED(); }
+  virtual void SetRootWindowTransformer(
+      scoped_ptr<RootWindowTransformer> transformer) {
+    transformer_helper_.SetRootWindowTransformer(transformer.Pass());
+  }
+  virtual aura::WindowTreeHost* AsWindowTreeHost() OVERRIDE { return this; }
+
+  // WindowTreeHostWin:
+  virtual void SetBounds(const gfx::Rect& bounds) OVERRIDE {
+    if (fullscreen_) {
+      saved_window_rect_.right = saved_window_rect_.left + bounds.width();
+      saved_window_rect_.bottom = saved_window_rect_.top + bounds.height();
+      return;
+    }
+    WindowTreeHostWin::SetBounds(bounds);
+  }
+  virtual void SetRootTransform(const gfx::Transform& transform) OVERRIDE {
+    transformer_helper_.SetTransform(transform);
+  }
+  gfx::Transform GetRootTransform() const {
+    return transformer_helper_.GetTransform();
+  }
+  virtual gfx::Transform GetInverseRootTransform() const OVERRIDE {
+    return transformer_helper_.GetInverseTransform();
+  }
+  virtual void UpdateRootWindowSize(const gfx::Size& host_size) OVERRIDE {
+    transformer_helper_.UpdateWindowSize(host_size);
+  }
+
+  bool fullscreen_;
+  RECT saved_window_rect_;
+  DWORD saved_window_style_;
+  DWORD saved_window_ex_style_;
+
+  TransformerHelper transformer_helper_;
+
+  DISALLOW_COPY_AND_ASSIGN(AshWindowTreeHostWin);
+};
+
+}  // namespace
+
+AshWindowTreeHost* AshWindowTreeHost::Create(const gfx::Rect& initial_bounds) {
+  if (base::win::GetVersion() >= base::win::VERSION_WIN8 &&
+      !CommandLine::ForCurrentProcess()->HasSwitch(
+          ash::switches::kForceAshToDesktop))
+    return AshRemoteWindowTreeHostWin::GetInstance();
+
+  return new AshWindowTreeHostWin(initial_bounds);
+}
+
+}  // namespace ash