Remove default arguments from CFX_FxgeDevice.

core/fxge/skia/fx_skia_device.h

 // Copyright 2014 PDFium 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 CORE_FXGE_SKIA_FX_SKIA_DEVICE_H_
 #define CORE_FXGE_SKIA_FX_SKIA_DEVICE_H_
 
 #if defined(_SKIA_SUPPORT_)
 
 class SkCanvas;
 class SkMatrix;
 class SkPaint;
 class SkPath;
 class SkPictureRecorder;
 struct SkIRect;
 
 class CFX_SkiaDeviceDriver : public IFX_RenderDeviceDriver {
  public:
   CFX_SkiaDeviceDriver(CFX_DIBitmap* pBitmap,
-                       int dither_bits,
                        FX_BOOL bRgbByteOrder,
                        CFX_DIBitmap* pOriDevice,
                        FX_BOOL bGroupKnockout);
-  CFX_SkiaDeviceDriver(SkPictureRecorder* recorder);
+  explicit CFX_SkiaDeviceDriver(SkPictureRecorder* recorder);
   CFX_SkiaDeviceDriver(int size_x, int size_y);
   ~CFX_SkiaDeviceDriver() override;
 
   /** Options */
   int GetDeviceCaps(int caps_id) override;
 
   /** Save and restore all graphic states */
   void SaveState() override;
   void RestoreState(bool bKeepSaved) override;
 
@@ skipping 103 matching lines @@
   void PaintStroke(SkPaint* spaint,
                    const CFX_GraphStateData* pGraphState,
                    const SkMatrix& matrix);
   SkPictureRecorder* GetRecorder() const { return m_pRecorder; }
 
  private:
   CFX_DIBitmap* m_pBitmap;
   CFX_DIBitmap* m_pOriDevice;
   SkCanvas* m_pCanvas;
   SkPictureRecorder* const m_pRecorder;
-  int m_ditherBits;
   FX_BOOL m_bRgbByteOrder;
   FX_BOOL m_bGroupKnockout;
 };
 #endif  // defined(_SKIA_SUPPORT_)
 
 #endif  // CORE_FXGE_SKIA_FX_SKIA_DEVICE_H_