Revert of UTF-8 detector for pages missing encoding info

third_party/WebKit/Source/wtf/text/UTF8.h

 /*
  * Copyright (C) 2007 Apple Inc.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 52 matching lines @@
 
 WTF_EXPORT ConversionResult convertUTF16ToUTF8(
     const UChar** sourceStart, const UChar* sourceEnd,
     char** targetStart, char* targetEnd, bool strict = true);
 
 WTF_EXPORT unsigned calculateStringHashAndLengthFromUTF8MaskingTop8Bits(const char* data, const char* dataEnd, unsigned& dataLength, unsigned& utf16Length);
 
 WTF_EXPORT bool equalUTF16WithUTF8(const UChar* a, const UChar* aEnd, const char* b, const char* bEnd);
 WTF_EXPORT bool equalLatin1WithUTF8(const LChar* a, const LChar* aEnd, const char* b, const char* bEnd);
 
-
-// Given a sequence of bytes in |data| of length |len|, check if the content is
-// encoded in UTF-8. Pure ASCII text is not regarded as UTF-8 in order to
-// respect the default encoding since it can be of any encoding.
-WTF_EXPORT bool isUTF8andNotASCII(const char* data, size_t length);
-
 } // namespace Unicode
 } // namespace WTF
 
 #endif // WTF_UTF8_h