Reland "UTF-8 detector for pages missing encoding info"

third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h

Index: third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h
diff --git a/third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h b/third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h
index 82411a707fd1ef085cb910d83d2ef7371f2fdc80..bdfa0d6b32791882175023408b1ff109e3246bbf 100644
--- a/third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h
+++ b/third_party/WebKit/Source/core/html/parser/TextResourceDecoder.h
@@ -79,16 +79,18 @@ public:
 
 private:
 
-    // TextResourceDecoder does three kind of encoding detection:
+    // TextResourceDecoder does four kinds of encoding detection:
     // 1. By BOM,
     // 2. By Content if |m_contentType| is not |PlainTextContext|
-    //    (e.g. <meta> tag for HTML), and
-    // 3. By detectTextEncoding().
+    //    (e.g. <meta> tag for HTML),
+    // 3. By isUTF8Encoded() to detect if the document
+    //    is of UTF-8, and
+    // 4. By detectTextEncodingUniversal().
     enum EncodingDetectionOption {
-        // Use 1. + 2. + 3.
+        // Use 1. + 2. + 4.
         UseAllAutoDetection,
 
-        // Use 1. + 2.
+        // Use 1. + 2. + 3.
         UseContentAndBOMBasedDetection,
 
         // Use None of them.
@@ -108,7 +110,8 @@ private:
     bool checkForCSSCharset(const char*, size_t, bool& movedDataToBuffer);
     bool checkForXMLCharset(const char*, size_t, bool& movedDataToBuffer);
     void checkForMetaCharset(const char*, size_t);
-    bool shouldAutoDetect() const;
+    void detectTextEncoding(const char*, size_t);
+    bool shouldDetectEncoding() const;
 
     ContentType m_contentType;
     WTF::TextEncoding m_encoding;