flesh out gradient shaders

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;
@@ skipping 110 matching lines @@
   FX_BOOL DrawDeviceText(int nChars,
                          const FXTEXT_CHARPOS* pCharPos,
                          CFX_Font* pFont,
                          CFX_FontCache* pCache,
                          const CFX_Matrix* pObject2Device,
                          FX_FLOAT font_size,
                          uint32_t color,
                          int alpha_flag = 0,
                          void* pIccTransform = NULL) override;
 
-  FX_BOOL DrawShading(CPDF_ShadingPattern* pPattern,
-                      CFX_Matrix* pMatrix,
+  FX_BOOL DrawShading(const CPDF_ShadingPattern* pPattern,
+                      const CFX_Matrix* pMatrix,
+                      const FX_RECT& clip_rect,
                       int alpha,
                       FX_BOOL bAlphaMode) override;
 
   virtual uint8_t* GetBuffer() const { return m_pBitmap->GetBuffer(); }
   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_