Cleanup CPDF_DIBSource::LoadColorInfo() and ValidateDictParam().

core/src/fpdfapi/fpdf_render/render_int.h

Index: core/src/fpdfapi/fpdf_render/render_int.h
diff --git a/core/src/fpdfapi/fpdf_render/render_int.h b/core/src/fpdfapi/fpdf_render/render_int.h
index d764c9a5ff17f1560fd1738b4dafdd400ad58aac..5b862b34019a34566bdd371294c402f2b512181c 100644
--- a/core/src/fpdfapi/fpdf_render/render_int.h
+++ b/core/src/fpdfapi/fpdf_render/render_int.h
@@ -561,8 +561,8 @@ class CPDF_DIBSource : public CFX_DIBSource {
   FX_BOOL m_bHasMask;
 
  private:
-  FX_BOOL LoadColorInfo(CPDF_Dictionary* pFormResources,
-                        CPDF_Dictionary* pPageResources);
+  bool LoadColorInfo(const CPDF_Dictionary* pFormResources,
+                     const CPDF_Dictionary* pPageResources);
   DIB_COMP_DATA* GetDecodeAndMaskArray(FX_BOOL& bDefaultDecode,
                                        FX_BOOL& bColorKey);
   CPDF_DIBSource* LoadMask(FX_DWORD& MatteColor);