Add missing operators for CFX_ByteStringC.

core/src/fpdfapi/fpdf_page/fpdf_page_graph_state.cpp

Index: core/src/fpdfapi/fpdf_page/fpdf_page_graph_state.cpp
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_graph_state.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_graph_state.cpp
index f79fcda0a0028fa62d1f3bd6e890ec2e9b385309..e098f66dec7d96f77ef42820a5da1ce5fcb02dd4 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_graph_state.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_graph_state.cpp
@@ -427,7 +427,7 @@ void CPDF_GeneralStateData::SetBlendMode(FX_BSTR blend_mode)
     if (blend_mode.GetLength() > 15) {
         return;
     }
-    FXSYS_memcpy32(m_BlendMode, (FX_LPCBYTE)blend_mode, blend_mode.GetLength());
+    FXSYS_memcpy32(m_BlendMode, blend_mode.GetPtr(), blend_mode.GetLength());
     m_BlendMode[blend_mode.GetLength()] = 0;
     m_BlendType = ::GetBlendType(blend_mode);
 }