Revert of UTF-8 detector for pages missing encoding info

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

Index: third_party/WebKit/Source/wtf/text/UTF8.h
diff --git a/third_party/WebKit/Source/wtf/text/UTF8.h b/third_party/WebKit/Source/wtf/text/UTF8.h
index b0ba7dbd9b563cc4380180c8cb007cb920b5880c..eda2633409ac290fdf75d8fac637f463ae78ddad 100644
--- a/third_party/WebKit/Source/wtf/text/UTF8.h
+++ b/third_party/WebKit/Source/wtf/text/UTF8.h
@@ -70,12 +70,6 @@
 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