Mark CFX_Font::IsSubstFontBold() as Skia-only.

Change-Id: I35a2ff4202d4b59ea0aa5816a5740039ac13b2da
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/68855
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
diff --git a/core/fxge/cfx_font.cpp b/core/fxge/cfx_font.cpp
index 2cef5ae..9e1d634 100644
--- a/core/fxge/cfx_font.cpp
+++ b/core/fxge/cfx_font.cpp
@@ -506,10 +506,12 @@
   return m_Face && FXFT_Is_Face_fixedwidth(m_Face->GetRec()) != 0;
 }
 
+#if defined _SKIA_SUPPORT_ || defined _SKIA_SUPPORT_PATHS_
 bool CFX_Font::IsSubstFontBold() const {
   CFX_SubstFont* subst_font = GetSubstFont();
   return subst_font && subst_font->GetOriginalWeight() >= FXFONT_FW_BOLD;
 }
+#endif
 
 ByteString CFX_Font::GetPsName() const {
   if (!m_Face)
diff --git a/core/fxge/cfx_font.h b/core/fxge/cfx_font.h
index d6fbc13..45ea79b 100644
--- a/core/fxge/cfx_font.h
+++ b/core/fxge/cfx_font.h
@@ -88,7 +88,9 @@
   bool IsItalic() const;
   bool IsBold() const;
   bool IsFixedWidth() const;
+#if defined _SKIA_SUPPORT_ || defined _SKIA_SUPPORT_PATHS_
   bool IsSubstFontBold() const;
+#endif
   bool IsVertical() const { return m_bVertical; }
   ByteString GetPsName() const;
   ByteString GetFamilyName() const;