views: Change CardUnmaskPromptViews::FadeOutView opacity to alpha.

chrome/browser/ui/views/autofill/card_unmask_prompt_views.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 CHROME_BROWSER_UI_VIEWS_AUTOFILL_CARD_UNMASK_PROMPT_VIEWS_H_
 #define CHROME_BROWSER_UI_VIEWS_AUTOFILL_CARD_UNMASK_PROMPT_VIEWS_H_
 
 #include "chrome/browser/ui/autofill/autofill_dialog_models.h"
 #include "chrome/browser/ui/autofill/card_unmask_prompt_view.h"
 #include "ui/gfx/animation/animation_delegate.h"
@@ skipping 69 matching lines @@
     FadeOutView();
     ~FadeOutView() override;
 
     // views::View
     void PaintChildren(const ui::PaintContext& context) override;
     void OnPaint(gfx::Canvas* canvas) override;
 
     void set_fade_everything(bool fade_everything) {
       fade_everything_ = fade_everything;
     }
-    void SetOpacity(double opacity);
+
+    // Set the alpha channel for this view. 0 is transparent and 255 is opaque.
+    void SetAlpha(uint8_t alpha);
 
    private:
     // Controls whether the background and border are faded out as well. Default
     // is false, meaning only children are faded.
     bool fade_everything_;
 
-    // On a scale of 0-1, how much to fade out the contents of this view. 0 is
-    // totally invisible, 1 is totally visible.
-    double opacity_;
+    // The alpha channel for this view. 0 is transparent and 255 is opaque.
+    uint8_t alpha_;
 
     DISALLOW_COPY_AND_ASSIGN(FadeOutView);
   };
 
   void InitIfNecessary();
   void SetRetriableErrorMessage(const base::string16& message);
   bool ExpirationDateIsValid() const;
   void SetInputsEnabled(bool enabled);
   void ClosePrompt();
 
@@ skipping 30 matching lines @@
   gfx::SlideAnimation overlay_animation_;
 
   base::WeakPtrFactory<CardUnmaskPromptViews> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(CardUnmaskPromptViews);
 };
 
 }  // namespace autofill
 
 #endif  // CHROME_BROWSER_UI_VIEWS_AUTOFILL_CARD_UNMASK_PROMPT_VIEWS_H_