Couple of changes for client area

ui/views/mus/desktop_window_tree_host_mus.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 "ui/views/mus/desktop_window_tree_host_mus.h"
 
 #include "base/memory/ptr_util.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/client/drag_drop_client.h"
 #include "ui/aura/client/focus_client.h"
@@ skipping 118 matching lines @@
   aura::Env::GetInstance()->RemoveObserver(this);
   desktop_native_widget_aura_->OnDesktopWindowTreeHostDestroyed(this);
 }
 
 bool DesktopWindowTreeHostMus::IsDocked() const {
   return window()->GetProperty(aura::client::kShowStateKey) ==
          ui::SHOW_STATE_DOCKED;
 }
 
 // TODO(erg): In addition to being called on system events, this also needs to
 // be called after window size changed.

[Elliot Glaysher, 2016/12/01 19:21:24]

I believe you can kill this todo now.

[sky, 2016/12/01 19:23:58]

Done.

 void DesktopWindowTreeHostMus::SendClientAreaToServer() {
   NonClientView* non_client_view =
       native_widget_delegate_->AsWidget()->non_client_view();
   if (!non_client_view || !non_client_view->client_view())
     return;
 
   const gfx::Rect client_area_rect(non_client_view->client_view()->bounds());
   SetClientArea(gfx::Insets(
       client_area_rect.y(), client_area_rect.x(),
       non_client_view->bounds().height() - client_area_rect.bottom(),
@@ skipping 20 matching lines @@
       ->GetDisplayNearestWindow(const_cast<aura::Window*>(window()))
       .device_scale_factor();
 }
 
 void DesktopWindowTreeHostMus::SetBoundsInDIP(const gfx::Rect& bounds_in_dip) {
   SetBoundsInPixels(gfx::ConvertRectToPixel(GetScaleFactor(), bounds_in_dip));
 }
 
 void DesktopWindowTreeHostMus::Init(aura::Window* content_window,
                                     const Widget::InitParams& params) {
+  // Needed so we don't render over the non-client area the window manager
+  // renders to.
+  content_window->layer()->SetFillsBoundsOpaquely(false);
   if (!params.bounds.IsEmpty())
     SetBoundsInDIP(params.bounds);
 }
 
 void DesktopWindowTreeHostMus::OnNativeWidgetCreated(
     const Widget::InitParams& params) {
   if (params.parent && params.parent->GetHost()) {
     parent_ = static_cast<DesktopWindowTreeHostMus*>(params.parent->GetHost());
     parent_->children_.insert(this);
   }
@@ skipping 343 matching lines @@
 }
 
 void DesktopWindowTreeHostMus::SizeConstraintsChanged() {
   int32_t behavior = ui::mojom::kResizeBehaviorNone;
   Widget* widget = native_widget_delegate_->AsWidget();
   if (widget->widget_delegate())
     behavior = widget->widget_delegate()->GetResizeBehavior();
   window()->SetProperty(aura::client::kResizeBehaviorKey, behavior);
 }
 
+bool DesktopWindowTreeHostMus::ShouldUpdateWindowTransparency() const {
+  // Needed so the window manager can render the client decorations.
+  return false;
+}
+
 void DesktopWindowTreeHostMus::OnWindowManagerFrameValuesChanged() {
   NonClientView* non_client_view =
       native_widget_delegate_->AsWidget()->non_client_view();
   if (non_client_view) {
     non_client_view->Layout();
     non_client_view->SchedulePaint();
   }
 
   SendClientAreaToServer();
   SendHitTestMaskToServer();
@@ skipping 19 matching lines @@
   if (GetBoundsInPixels().size() != bounds_in_pixels.size()) {
     gfx::Size size = bounds_in_pixels.size();
     size.SetToMax(gfx::ConvertSizeToPixel(
         GetScaleFactor(), native_widget_delegate_->GetMinimumSize()));
     const gfx::Size max_size_in_pixels = gfx::ConvertSizeToPixel(
         GetScaleFactor(), native_widget_delegate_->GetMaximumSize());
     if (!max_size_in_pixels.IsEmpty())
       size.SetToMin(max_size_in_pixels);
     final_bounds_in_pixels.set_size(size);
   }
+  const gfx::Rect old_bounds_in_pixels = GetBoundsInPixels();
   WindowTreeHostMus::SetBoundsInPixels(final_bounds_in_pixels);
+  if (old_bounds_in_pixels.size() != final_bounds_in_pixels.size()) {
+    SendClientAreaToServer();
+    SendHitTestMaskToServer();
+  }
 }
 
 void DesktopWindowTreeHostMus::OnWindowInitialized(aura::Window* window) {}
 
 void DesktopWindowTreeHostMus::OnActiveFocusClientChanged(
     aura::client::FocusClient* focus_client,
     aura::Window* window) {
   if (window == this->window()) {
     is_active_ = true;
     desktop_native_widget_aura_->HandleActivationChanged(true);
   } else if (is_active_) {
     is_active_ = false;
     desktop_native_widget_aura_->HandleActivationChanged(false);
   }
 }
 
 }  // namespace views