Use VTTScanner for VTT cue settings parsing

Source/core/html/track/vtt/VTTScanner.h

 /*
  * Copyright (c) 2013, Opera Software ASA. 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 40 matching lines @@
 public:
     explicit VTTScanner(const String& line);
 
     typedef const LChar* Position;
 
     class Run {
     public:
         Run(Position start, Position end, bool is8Bit)
             : m_start(start), m_end(end), m_is8Bit(is8Bit) { }
 
+        Position start() const { return m_start; }
         Position end() const { return m_end; }
 
         bool isEmpty() const { return m_start == m_end; }
         size_t length() const;
 
     private:
         Position m_start;
         Position m_end;
         bool m_is8Bit;
     };
@@ skipping 18 matching lines @@
     // the end of the input.
     template<bool characterPredicate(UChar)>
     void skipWhile();
 
     // Return the run of characters for which the specified
     // |characterPredicate| returns true. The start of the run will be the
     // current input pointer.
     template<bool characterPredicate(UChar)>
     Run collectWhile();
 
+    // Like collectWhile, but using a negated predicate.
+    template<bool characterPredicate(UChar)>
+    Run collectUntil();
+
+    // Scan the string |toMatch|, using the specified |run| as the sequence to
+    // match against.
+    bool scanRun(const Run&, const String& toMatch);
+
+    // Skip to the end of the specified |run|.
+    void skipRun(const Run&);
+
+    // Return the String made up of the characters in |run|, and advance the
+    // input pointer to the end of the run.
+    String extractString(const Run&);
+
     // Return a String constructed from the rest of the input (between input
     // pointer and end of input), and advance the input pointer accordingly.
     String restOfInputAsString();
 
     // Scan a set of ASCII digits from the input. Return the number of digits
     // scanned, and set |number| to the computed value. If the digits make up a
     // number that does not fit the 'int' type, |number| is set to INT_MAX.
     // Note: Does not handle sign.
     unsigned scanDigits(int& number);
 
@@ skipping 46 matching lines @@
     if (m_is8Bit) {
         const LChar* current = m_data.characters8;
         ::skipWhile<LChar, LCharPredicateAdapter<characterPredicate> >(current, m_end.characters8);
         return Run(position(), current, m_is8Bit);
     }
     const UChar* current = m_data.characters16;
     ::skipWhile<UChar, characterPredicate>(current, m_end.characters16);
     return Run(position(), reinterpret_cast<Position>(current), m_is8Bit);
 }
 
+template<bool characterPredicate(UChar)>
+inline VTTScanner::Run VTTScanner::collectUntil()
+{
+    if (m_is8Bit) {
+        const LChar* current = m_data.characters8;
+        ::skipUntil<LChar, LCharPredicateAdapter<characterPredicate> >(current, m_end.characters8);
+        return Run(position(), current, m_is8Bit);
+    }
+    const UChar* current = m_data.characters16;
+    ::skipUntil<UChar, characterPredicate>(current, m_end.characters16);
+    return Run(position(), reinterpret_cast<Position>(current), m_is8Bit);
+}
+
 inline void VTTScanner::seekTo(Position position)
 {
     ASSERT(position <= end());
     m_data.characters8 = position;
 }
 
 inline UChar VTTScanner::currentChar() const
 {
     ASSERT(position() < end());
     return m_is8Bit ? *m_data.characters8 : *m_data.characters16;
@@ skipping 37 matching lines @@
     unsigned* m_outPosition;
     union {
         const LChar* characters8;
         const UChar* characters16;
     } m_start;
 };
 
 }
 
 #endif