Kill scattered extern _PDF_CharType declarations.

core/src/fpdfapi/fpdf_parser/fpdf_parser_filters.cpp

Index: core/src/fpdfapi/fpdf_parser/fpdf_parser_filters.cpp
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_filters.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_filters.cpp
index 610fb397815e846403b07b1fe6124d4f216f5c71..d17b1237652c258099d9b49932f626eb9d3e157e 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_filters.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_filters.cpp
@@ -576,12 +576,11 @@ CPDF_Ascii85Filter::CPDF_Ascii85Filter()
     m_State = 0;
     m_CharCount = 0;
 }
-extern const FX_LPCSTR _PDF_CharType;
 void CPDF_Ascii85Filter::v_FilterIn(FX_LPCBYTE src_buf, FX_DWORD src_size, CFX_BinaryBuf& dest_buf)
 {
     for (FX_DWORD i = 0; i < src_size; i ++) {
         FX_BYTE byte = src_buf[i];
-        if (_PDF_CharType[byte] == 'W') {
+        if (PDF_CharType[byte] == 'W') {
             continue;
         }
         switch (m_State) {
@@ -640,7 +639,7 @@ void CPDF_AsciiHexFilter::v_FilterIn(FX_LPCBYTE src_buf, FX_DWORD src_size, CFX_
 {
     for (FX_DWORD i = 0; i < src_size; i ++) {
         FX_BYTE byte = src_buf[i];
-        if (_PDF_CharType[byte] == 'W') {
+        if (PDF_CharType[byte] == 'W') {
             continue;
         }
         int digit;