Add configuration_changed event and set_background_opacity request.

components/exo/shell_surface.h

 // Copyright 2015 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 COMPONENTS_EXO_SHELL_SURFACE_H_
 #define COMPONENTS_EXO_SHELL_SURFACE_H_
 
 #include <deque>
 #include <memory>
 #include <string>
@@ skipping 129 matching lines @@
   void Close();
 
   // Set geometry for surface. The geometry represents the "visible bounds"
   // for the surface from the user's perspective.
   void SetGeometry(const gfx::Rect& geometry);
 
   // Set the content bounds for the shadow. Empty bounds will delete
   // the shadow.
   void SetRectangularShadow(const gfx::Rect& content_bounds);
 
+  // Set the pacity of the background for the window that has a shadow.
+  void SetRectangularShadowBackgroundOpacity(float opacity);
+
   // Set scale factor for surface. The scale factor will be applied to surface
   // and all descendants.
   void SetScale(double scale);
 
   // Set top inset for surface.
   void SetTopInset(int height);
 
   // Sets the main surface for the window.
   static void SetMainSurface(aura::Window* window, Surface* surface);
 
@@ skipping 46 matching lines @@
       aura::Window* gained_active,
       aura::Window* lost_active) override;
 
   // Overridden from ui::EventHandler:
   void OnKeyEvent(ui::KeyEvent* event) override;
   void OnMouseEvent(ui::MouseEvent* event) override;
 
   // Overridden from ui::AcceleratorTarget:
   bool AcceleratorPressed(const ui::Accelerator& accelerator) override;
 
+  const aura::Window* shadow_underlay_for_test() const {
+    return shadow_underlay_;
+  }
+
  private:
   class ScopedConfigure;
   class ScopedAnimationsDisabled;
 
   // Surface state associated with each configure request.
   struct Config {
     uint32_t serial;
     gfx::Vector2d origin_offset;
     int resize_component;
   };
@@ skipping 55 matching lines @@
   int resize_component_ = HTCAPTION;  // HT constant (see ui/base/hit_test.h)
   int pending_resize_component_ = HTCAPTION;
   aura::Window* shadow_overlay_ = nullptr;
   aura::Window* shadow_underlay_ = nullptr;
   gfx::Rect shadow_content_bounds_;
   std::deque<Config> pending_configs_;
   std::unique_ptr<ash::WindowResizer> resizer_;
   std::unique_ptr<ScopedAnimationsDisabled> scoped_animations_disabled_;
   int top_inset_height_ = 0;
   int pending_top_inset_height_ = 0;
+  float rectangular_shadow_background_opacity_ = 1.0;
 
   DISALLOW_COPY_AND_ASSIGN(ShellSurface);
 };
 
 }  // namespace exo
 
 #endif  // COMPONENTS_EXO_SHELL_SURFACE_H_