Change chrome:// favicons in tabstrip based on theming.

chrome/browser/ui/cocoa/download/background_theme.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 CHROME_BROWSER_UI_COCOA_DOWNLOAD_BACKGROUND_THEME_H_
 #define CHROME_BROWSER_UI_COCOA_DOWNLOAD_BACKGROUND_THEME_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/mac/scoped_nsobject.h"
 #include "ui/base/theme_provider.h"
 
 class BackgroundTheme : public ui::ThemeProvider {
  public:
   BackgroundTheme(const ui::ThemeProvider* provider);
   ~BackgroundTheme() override;
 
   // Overridden from ui::ThemeProvider:
   bool UsingSystemTheme() const override;
   gfx::ImageSkia* GetImageSkiaNamed(int id) const override;
   SkColor GetColor(int id) const override;
+  color_utils::HSL GetTint(int id) const override;
   int GetDisplayProperty(int id) const override;
   bool ShouldUseNativeFrame() const override;
   bool HasCustomImage(int id) const override;
   base::RefCountedMemory* GetRawData(int id, ui::ScaleFactor scale_factor)
       const override;
   bool InIncognitoMode() const override;
   bool HasCustomColor(int id) const override;
   NSImage* GetNSImageNamed(int id) const override;
   NSColor* GetNSImageColorNamed(int id) const override;
   NSColor* GetNSColor(int id) const override;
   NSColor* GetNSColorTint(int id) const override;
   NSGradient* GetNSGradient(int id) const override;
   bool ShouldIncreaseContrast() const override;
 
  private:
   const ui::ThemeProvider* provider_;
   base::scoped_nsobject<NSGradient> buttonGradient_;
   base::scoped_nsobject<NSGradient> buttonPressedGradient_;
   base::scoped_nsobject<NSColor> borderColor_;
 };
 
 #endif  // CHROME_BROWSER_UI_COCOA_DOWNLOAD_BACKGROUND_THEME_H_