diff --git content/browser/renderer_host/render_widget_host_view_base.cc content/browser/renderer_host/render_widget_host_view_base.cc
index 151c87cd72e3..593a79904382 100644
--- content/browser/renderer_host/render_widget_host_view_base.cc
+++ content/browser/renderer_host/render_widget_host_view_base.cc
@@ -312,6 +312,14 @@ float RenderWidgetHostViewBase::GetDeviceScaleFactor() const {
   return screen_info.device_scale_factor;
 }
 
+void RenderWidgetHostViewBase::SetHasExternalParent(bool val) {
+  has_external_parent_ = val;
+}
+
+bool RenderWidgetHostViewBase::HasExternalParent() const {
+  return has_external_parent_;
+}
+
 uint32_t RenderWidgetHostViewBase::RendererFrameNumber() {
   return renderer_frame_number_;
 }
diff --git content/browser/renderer_host/render_widget_host_view_base.h content/browser/renderer_host/render_widget_host_view_base.h
index 06f2793aa2d7..06244d674026 100644
--- content/browser/renderer_host/render_widget_host_view_base.h
+++ content/browser/renderer_host/render_widget_host_view_base.h
@@ -79,6 +79,7 @@ class BrowserAccessibilityManager;
 class CursorManager;
 class RenderWidgetHostImpl;
 class RenderWidgetHostViewBaseObserver;
+class RenderWidgetHostViewGuest;
 class SyntheticGestureTarget;
 class TextInputManager;
 class TouchSelectionControllerClientManager;
@@ -98,6 +99,9 @@ class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
   float current_device_scale_factor() const {
     return current_device_scale_factor_;
   }
+  void set_current_device_scale_factor(float scale_factor) {
+    current_device_scale_factor_ = scale_factor;
+  }
 
   // Returns the focused RenderWidgetHost inside this |view|'s RWH.
   RenderWidgetHostImpl* GetFocusedWidget() const;
@@ -122,6 +126,8 @@ class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
                           bool editable) override;
   void GetScreenInfo(ScreenInfo* screen_info) const override;
   float GetDeviceScaleFactor() const final;
+  void SetHasExternalParent(bool val) override;
+  bool HasExternalParent() const override;
   TouchSelectionControllerClientManager*
   GetTouchSelectionControllerClientManager() override;
 
@@ -412,6 +418,12 @@ class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
   // helps to position the full screen widget on the correct monitor.
   virtual void InitAsFullscreen(RenderWidgetHostView* reference_host_view) = 0;
 
+  // Perform all the initialization steps necessary for this object to represent
+  // the platform widget owned by |guest_view| and embedded in
+  // |parent_host_view|.
+  virtual void InitAsGuest(RenderWidgetHostView* parent_host_view,
+                           RenderWidgetHostViewGuest* guest_view) {}
+
   // Sets the cursor for this view to the one associated with the specified
   // cursor_type.
   virtual void UpdateCursor(const WebCursor& cursor) = 0;
@@ -559,6 +571,10 @@ class CONTENT_EXPORT RenderWidgetHostViewBase : public RenderWidgetHostView,
 
   WebContentsAccessibility* web_contents_accessibility_;
 
+  // True if the widget has a external parent view/window outside of the
+  // Chromium-controlled view/window hierarchy.
+  bool has_external_parent_;
+
  private:
 #if defined(USE_AURA)
   void OnDidScheduleEmbed(int routing_id,
diff --git content/browser/renderer_host/render_widget_host_view_event_handler.cc content/browser/renderer_host/render_widget_host_view_event_handler.cc
index 8318ed172a75..0d6023427bf4 100644
--- content/browser/renderer_host/render_widget_host_view_event_handler.cc
+++ content/browser/renderer_host/render_widget_host_view_event_handler.cc
@@ -28,6 +28,10 @@
 #include "ui/events/blink/web_input_event.h"
 #include "ui/touch_selection/touch_selection_controller.h"
 
+#if defined(OS_LINUX)
+#include "ui/aura/window_tree_host.h"
+#endif
+
 #if defined(OS_WIN)
 #include "content/browser/frame_host/render_frame_host_impl.h"
 #include "content/public/common/context_menu_params.h"
@@ -880,6 +884,14 @@ void RenderWidgetHostViewEventHandler::SetKeyboardFocus() {
         ::SetFocus(hwnd);
     }
   }
+#endif
+#if defined(OS_LINUX)
+  if (host_view_->HasExternalParent() &&
+      window_ && window_->delegate()->CanFocus()) {
+    aura::WindowTreeHost* host = window_->GetHost();
+    if (host)
+      host->Show();
+  }
 #endif
   // TODO(wjmaclean): can host_ ever be null?
   if (host_ && set_focus_on_mouse_down_or_key_event_) {
diff --git content/public/browser/render_widget_host_view.h content/public/browser/render_widget_host_view.h
index e967efe6ad9b..3c49ea9ac980 100644
--- content/public/browser/render_widget_host_view.h
+++ content/public/browser/render_widget_host_view.h
@@ -213,6 +213,14 @@ class CONTENT_EXPORT RenderWidgetHostView {
   // This must always return the same device scale factor as GetScreenInfo.
   virtual float GetDeviceScaleFactor() const = 0;
 
+  // Set whether the widget has a external parent view/window outside of the
+  // Chromium-controlled view/window hierarchy.
+  virtual void SetHasExternalParent(bool val) = 0;
+
+  // Returns true if the widget has a external parent view/window outside of the
+  // Chromium-controlled view/window hierarchy.
+  virtual bool HasExternalParent() const = 0;
+
 #if defined(OS_MACOSX)
   // Set the view's active state (i.e., tint state of controls).
   virtual void SetActive(bool active) = 0;
diff --git ui/views/widget/desktop_aura/desktop_screen_win.cc ui/views/widget/desktop_aura/desktop_screen_win.cc
index f772f64d656e..7d13f9f81b6c 100644
--- ui/views/widget/desktop_aura/desktop_screen_win.cc
+++ ui/views/widget/desktop_aura/desktop_screen_win.cc
@@ -32,6 +32,8 @@ display::Display DesktopScreenWin::GetDisplayMatching(
 }
 
 HWND DesktopScreenWin::GetHWNDFromNativeView(gfx::NativeView window) const {
+  if (!window)
+    return NULL;
   aura::WindowTreeHost* host = window->GetHost();
   return host ? host->GetAcceleratedWidget() : NULL;
 }
diff --git ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
index 19f103c0385e..737125f8f601 100644
--- ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
+++ ui/views/widget/desktop_aura/desktop_window_tree_host_win.cc
@@ -86,6 +86,7 @@ DesktopWindowTreeHostWin::DesktopWindowTreeHostWin(
       should_animate_window_close_(false),
       pending_close_(false),
       has_non_client_view_(false),
+      has_external_parent_(false),
       tooltip_(NULL) {
 }
 
@@ -124,8 +125,12 @@ void DesktopWindowTreeHostWin::Init(aura::Window* content_window,
                         native_widget_delegate_);
 
   HWND parent_hwnd = NULL;
-  if (params.parent && params.parent->GetHost())
+  if (params.parent_widget) {
+    parent_hwnd = params.parent_widget;
+    has_external_parent_ = true;
+  } else if (params.parent && params.parent->GetHost()) {
     parent_hwnd = params.parent->GetHost()->GetAcceleratedWidget();
+  }
 
   remove_standard_frame_ = params.remove_standard_frame;
   has_non_client_view_ = Widget::RequiresNonClientView(params.type);
@@ -849,11 +854,15 @@ void DesktopWindowTreeHostWin::HandleFrameChanged() {
 }
 
 void DesktopWindowTreeHostWin::HandleNativeFocus(HWND last_focused_window) {
-  // TODO(beng): inform the native_widget_delegate_.
+  // See comments in CefBrowserHostImpl::PlatformSetFocus.
+  if (has_external_parent_ && CanActivate())
+    HandleActivationChanged(true);
 }
 
 void DesktopWindowTreeHostWin::HandleNativeBlur(HWND focused_window) {
-  // TODO(beng): inform the native_widget_delegate_.
+  // See comments in CefBrowserHostImpl::PlatformSetFocus.
+  if (has_external_parent_ && CanActivate())
+    HandleActivationChanged(false);
 }
 
 bool DesktopWindowTreeHostWin::HandleMouseEvent(const ui::MouseEvent& event) {
diff --git ui/views/widget/desktop_aura/desktop_window_tree_host_win.h ui/views/widget/desktop_aura/desktop_window_tree_host_win.h
index 732f492c102f..a7007468c3b7 100644
--- ui/views/widget/desktop_aura/desktop_window_tree_host_win.h
+++ ui/views/widget/desktop_aura/desktop_window_tree_host_win.h
@@ -277,6 +277,10 @@ class VIEWS_EXPORT DesktopWindowTreeHostWin
   // True if the window should have the frame removed.
   bool remove_standard_frame_;
 
+  // True if the widget has a external parent view/window outside of the
+  // Chromium-controlled view/window hierarchy.
+  bool has_external_parent_;
+
   // Owned by TooltipController, but we need to forward events to it so we keep
   // a reference.
   corewm::TooltipWin* tooltip_;
diff --git ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
index f8550833ee6f..117a47a7aacd 100644
--- ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
+++ ui/views/widget/desktop_aura/desktop_window_tree_host_x11.cc
@@ -145,6 +145,7 @@ DesktopWindowTreeHostX11::DesktopWindowTreeHostX11(
       use_native_frame_(false),
       should_maximize_after_map_(false),
       use_argb_visual_(false),
+      has_external_parent_(false),
       drag_drop_client_(NULL),
       native_widget_delegate_(native_widget_delegate),
       desktop_native_widget_aura_(desktop_native_widget_aura),
@@ -158,6 +159,7 @@ DesktopWindowTreeHostX11::DesktopWindowTreeHostX11(
       has_window_focus_(false),
       has_pointer_focus_(false),
       modal_dialog_counter_(0),
+      xwindow_destroyed_(false),
       close_widget_factory_(this),
       weak_factory_(this) {}
 
@@ -193,6 +195,8 @@ std::vector<aura::Window*> DesktopWindowTreeHostX11::GetAllOpenWindows() {
 }
 
 gfx::Rect DesktopWindowTreeHostX11::GetX11RootWindowBounds() const {
+  if (!screen_bounds_.IsEmpty())
+    return screen_bounds_;
   return bounds_in_pixels_;
 }
 
@@ -505,7 +509,8 @@ void DesktopWindowTreeHostX11::CloseNow() {
   // Actually free our native resources.
   if (ui::PlatformEventSource::GetInstance())
     ui::PlatformEventSource::GetInstance()->RemovePlatformEventDispatcher(this);
-  XDestroyWindow(xdisplay_, xwindow_);
+  if (!xwindow_destroyed_)
+    XDestroyWindow(xdisplay_, xwindow_);
   xwindow_ = x11::None;
 
   desktop_native_widget_aura_->OnHostClosed();
@@ -646,6 +651,8 @@ void DesktopWindowTreeHostX11::GetWindowPlacement(
 }
 
 gfx::Rect DesktopWindowTreeHostX11::GetWindowBoundsInScreen() const {
+  if (!screen_bounds_.IsEmpty())
+    return screen_bounds_;
   return ToDIPRect(bounds_in_pixels_);
 }
 
@@ -1253,6 +1260,8 @@ void DesktopWindowTreeHostX11::SetBoundsInPixels(
 }
 
 gfx::Point DesktopWindowTreeHostX11::GetLocationOnScreenInPixels() const {
+  if (!screen_bounds_.IsEmpty())
+    return screen_bounds_.origin();
   return bounds_in_pixels_.origin();
 }
 
@@ -1364,7 +1373,6 @@ void DesktopWindowTreeHostX11::InitX11Window(
   ::Atom window_type;
   switch (params.type) {
     case Widget::InitParams::TYPE_MENU:
-      swa.override_redirect = x11::True;
       window_type = gfx::GetAtom("_NET_WM_WINDOW_TYPE_MENU");
       break;
     case Widget::InitParams::TYPE_TOOLTIP:
@@ -1420,9 +1428,15 @@ void DesktopWindowTreeHostX11::InitX11Window(
   attribute_mask |= CWBorderPixel;
   swa.border_pixel = 0;
 
+  gfx::AcceleratedWidget parent_widget = params.parent_widget;
+  if (parent_widget == gfx::kNullAcceleratedWidget)
+    parent_widget = x_root_window_;
+  else
+    has_external_parent_ = true;
+
   bounds_in_pixels_ = ToPixelRect(params.bounds);
   bounds_in_pixels_.set_size(AdjustSize(bounds_in_pixels_.size()));
-  xwindow_ = XCreateWindow(xdisplay_, x_root_window_, bounds_in_pixels_.x(),
+  xwindow_ = XCreateWindow(xdisplay_, parent_widget, bounds_in_pixels_.x(),
                            bounds_in_pixels_.y(), bounds_in_pixels_.width(),
                            bounds_in_pixels_.height(),
                            0,  // border width
@@ -2020,6 +2034,10 @@ uint32_t DesktopWindowTreeHostX11::DispatchEvent(
       }
       break;
     }
+    case DestroyNotify:
+      xwindow_destroyed_ = true;
+      CloseNow();
+      break;
     case x11::FocusIn:
     case x11::FocusOut:
       OnFocusEvent(xev->type == x11::FocusIn, event->xfocus.mode,
diff --git ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h
index 021a1d9ad2b1..7f8ccfb73acd 100644
--- ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h
+++ ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h
@@ -86,6 +86,12 @@ class VIEWS_EXPORT DesktopWindowTreeHostX11
   // Disables event listening to make |dialog| modal.
   std::unique_ptr<base::Closure> DisableEventListening();
 
+  void set_screen_bounds(const gfx::Rect& bounds) { screen_bounds_ = bounds; }
+
+  // Returns true if the widget has a external parent view/window outside of the
+  // Chromium-controlled view/window hierarchy.
+  bool has_external_parent() const { return has_external_parent_; }
+
  protected:
   // Overridden from DesktopWindowTreeHost:
   void Init(aura::Window* content_window,
@@ -302,6 +308,9 @@ class VIEWS_EXPORT DesktopWindowTreeHostX11
   // The bounds of |xwindow_|.
   gfx::Rect bounds_in_pixels_;
 
+  // Override the screen bounds when the host is a child window.
+  gfx::Rect screen_bounds_;
+
   // Whenever the bounds are set, we keep the previous set of bounds around so
   // we can have a better chance of getting the real
   // |restored_bounds_in_pixels_|. Window managers tend to send a Configure
@@ -341,6 +350,10 @@ class VIEWS_EXPORT DesktopWindowTreeHostX11
   // Whether we used an ARGB visual for our window.
   bool use_argb_visual_;
 
+  // True if the widget has a external parent view/window outside of the
+  // Chromium-controlled view/window hierarchy.
+  bool has_external_parent_;
+
   DesktopDragDropClientAuraX11* drag_drop_client_;
 
   std::unique_ptr<ui::EventHandler> x11_non_client_event_filter_;
@@ -431,6 +444,9 @@ class VIEWS_EXPORT DesktopWindowTreeHostX11
 
   uint32_t modal_dialog_counter_;
 
+  // True if the xwindow has already been destroyed.
+  bool xwindow_destroyed_;
+
   base::WeakPtrFactory<DesktopWindowTreeHostX11> close_widget_factory_;
   base::WeakPtrFactory<DesktopWindowTreeHostX11> weak_factory_;
 
diff --git ui/views/widget/widget.cc ui/views/widget/widget.cc
index 926519dfa332..e06be5a1b0eb 100644
--- ui/views/widget/widget.cc
+++ ui/views/widget/widget.cc
@@ -130,6 +130,7 @@ Widget::InitParams::InitParams(Type type)
       use_system_default_icon(false),
       show_state(ui::SHOW_STATE_DEFAULT),
       parent(nullptr),
+      parent_widget(gfx::kNullAcceleratedWidget),
       native_widget(nullptr),
       desktop_window_tree_host(nullptr),
       layer_type(ui::LAYER_TEXTURED),
@@ -304,7 +305,7 @@ void Widget::Init(const InitParams& in_params) {
     params.name = params.delegate->GetContentsView()->GetClassName();
 
   params.child |= (params.type == InitParams::TYPE_CONTROL);
-  is_top_level_ = !params.child;
+  is_top_level_ = !params.child || params.parent_widget;
 
   if (params.opacity == views::Widget::InitParams::INFER_OPACITY &&
       params.type != views::Widget::InitParams::TYPE_WINDOW &&
@@ -368,7 +369,12 @@ void Widget::Init(const InitParams& in_params) {
     }
   } else if (params.delegate) {
     SetContentsView(params.delegate->GetContentsView());
-    SetInitialBoundsForFramelessWindow(params.bounds);
+    if (params.parent_widget) {
+      // Set the bounds directly instead of applying an inset.
+      SetBounds(params.bounds);
+    } else {
+      SetInitialBoundsForFramelessWindow(params.bounds);
+    }
   }
   // This must come after SetContentsView() or it might not be able to find
   // the correct NativeTheme (on Linux). See http://crbug.com/384492
@@ -1098,10 +1104,16 @@ void Widget::OnNativeWidgetDestroyed() {
 }
 
 gfx::Size Widget::GetMinimumSize() const {
+  gfx::Size size;
+  if (widget_delegate_->MaybeGetMinimumSize(&size))
+    return size;
   return non_client_view_ ? non_client_view_->GetMinimumSize() : gfx::Size();
 }
 
 gfx::Size Widget::GetMaximumSize() const {
+  gfx::Size size;
+  if (widget_delegate_->MaybeGetMaximumSize(&size))
+    return size;
   return non_client_view_ ? non_client_view_->GetMaximumSize() : gfx::Size();
 }
 
diff --git ui/views/widget/widget.h ui/views/widget/widget.h
index 6c0c60807a2b..87ed97b90ab5 100644
--- ui/views/widget/widget.h
+++ ui/views/widget/widget.h
@@ -252,6 +252,7 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
     // Whether the widget should be maximized or minimized.
     ui::WindowShowState show_state;
     gfx::NativeView parent;
+    gfx::AcceleratedWidget parent_widget;
     // Specifies the initial bounds of the Widget. Default is empty, which means
     // the NativeWidget may specify a default size. If the parent is specified,
     // |bounds| is in the parent's coordinate system. If the parent is not
diff --git ui/views/widget/widget_delegate.h ui/views/widget/widget_delegate.h
index 8ae821974838..c73b20dcb9b0 100644
--- ui/views/widget/widget_delegate.h
+++ ui/views/widget/widget_delegate.h
@@ -183,6 +183,10 @@ class VIEWS_EXPORT WidgetDelegate {
   // be cycled through with keyboard focus.
   virtual void GetAccessiblePanes(std::vector<View*>* panes) {}
 
+  // CEF supports override of min/max size values.
+  virtual bool MaybeGetMinimumSize(gfx::Size* size) const { return false; }
+  virtual bool MaybeGetMaximumSize(gfx::Size* size) const { return false; }
+
  protected:
   virtual ~WidgetDelegate() {}
 
diff --git ui/views/widget/widget_hwnd_utils.cc ui/views/widget/widget_hwnd_utils.cc
index c7296fed234d..244d0034a1c4 100644
--- ui/views/widget/widget_hwnd_utils.cc
+++ ui/views/widget/widget_hwnd_utils.cc
@@ -73,7 +73,7 @@ void CalculateWindowStylesFromInitParams(
       if (!widget_delegate->CanResize())
         *style &= ~(WS_THICKFRAME | WS_MAXIMIZEBOX);
       if (params.remove_standard_frame)
-        *style &= ~(WS_MINIMIZEBOX | WS_MAXIMIZEBOX);
+        *style &= ~(WS_MINIMIZEBOX | WS_MAXIMIZEBOX | WS_CAPTION | WS_SYSMENU);
 
       if (native_widget_delegate->IsDialogBox()) {
         *style |= DS_MODALFRAME;
diff --git ui/views/win/hwnd_message_handler.cc ui/views/win/hwnd_message_handler.cc
index c8fb7eecb9c8..49c0bc6c5f60 100644
--- ui/views/win/hwnd_message_handler.cc
+++ ui/views/win/hwnd_message_handler.cc
@@ -2687,8 +2687,12 @@ LRESULT HWNDMessageHandler::HandleMouseEventInternal(UINT message,
     active_mouse_tracking_flags_ = 0;
   } else if (event.type() == ui::ET_MOUSEWHEEL) {
     // Reroute the mouse wheel to the window under the pointer if applicable.
-    return (ui::RerouteMouseWheel(hwnd(), w_param, l_param) ||
-            delegate_->HandleMouseEvent(ui::MouseWheelEvent(msg))) ? 0 : 1;
+    if (ui::RerouteMouseWheel(hwnd(), w_param, l_param) ||
+        delegate_->HandleMouseEvent(ui::MouseWheelEvent(msg))) {
+      SetMsgHandled(TRUE);
+      return 0;
+    }
+    return 1;
   }
 
   // There are cases where the code handling the message destroys the window,