Converts Widget::SetOpacity from char to float

ui/views/widget/desktop_aura/desktop_window_tree_host_win.h

 // Copyright (c) 2012 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 UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_WIN_H_
 #define UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_WIN_H_
 
 #include "base/macros.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/views/views_export.h"
@@ skipping 76 matching lines @@
       const gfx::Vector2d& drag_offset,
       Widget::MoveLoopSource source,
       Widget::MoveLoopEscapeBehavior escape_behavior) override;
   void EndMoveLoop() override;
   void SetVisibilityChangedAnimationsEnabled(bool value) override;
   bool ShouldUseNativeFrame() const override;
   bool ShouldWindowContentsBeTransparent() const override;
   void FrameTypeChanged() override;
   void SetFullscreen(bool fullscreen) override;
   bool IsFullscreen() const override;
-  void SetOpacity(unsigned char opacity) override;
+  void SetOpacity(float opacity) override;
   void SetWindowIcons(const gfx::ImageSkia& window_icon,
                       const gfx::ImageSkia& app_icon) override;
   void InitModalType(ui::ModalType modal_type) override;
   void FlashFrame(bool flash_frame) override;
   void OnRootViewLayout() override;
   void OnNativeWidgetFocus() override;
   void OnNativeWidgetBlur() override;
   bool IsAnimatingClosed() const override;
   bool IsTranslucentWindowOpacitySupported() const override;
   void SizeConstraintsChanged() override;
@@ skipping 157 matching lines @@
   // Indicates if current window will receive mouse events when should not
   // become activated.
   bool wants_mouse_events_when_inactive_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(DesktopWindowTreeHostWin);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_DESKTOP_AURA_DESKTOP_WINDOW_TREE_HOST_WIN_H_