Remove unimplemented CPDF_DocPageData::Clear() declaration.

No longer exists.

Change-Id: I664a1dfcef26db34d0ad681fe6d91ea9af1eb8fb
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/79391
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>
diff --git a/core/fpdfapi/page/cpdf_docpagedata.h b/core/fpdfapi/page/cpdf_docpagedata.h
index 307f17e..c382308 100644
--- a/core/fpdfapi/page/cpdf_docpagedata.h
+++ b/core/fpdfapi/page/cpdf_docpagedata.h
@@ -100,7 +100,6 @@
       int charset,
       ByteString basefont,
       std::function<void(wchar_t, wchar_t, CPDF_Array*)> Insert);
-  void Clear(bool bForceRelease);
 
   bool m_bForceClear = false;