Fix TimeRanges::nearest() to actually calculate nearest time.

Source/core/html/TimeRanges.h

 /*
  * Copyright (C) 2007, 2009 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 91 matching lines @@
     void unionWith(const TimeRanges*);
 
     unsigned length() const { return m_ranges.size(); }
     double start(unsigned index, ExceptionState&) const;
     double end(unsigned index, ExceptionState&) const;
 
     void add(double start, double end);
 
     bool contain(double time) const;
 
-    double nearest(double time) const;
+    double nearest(double newPlaybackPosition, double currentPlaybackPosition) const;
 
     void trace(Visitor*);
 
 private:
     TimeRanges() { }
 
     TimeRanges(double start, double end);
 
     void invert();
 
     WillBeHeapVector<Range> m_ranges;
 };
 
 } // namespace blink
 
 WTF_ALLOW_MOVE_AND_INIT_WITH_MEM_FUNCTIONS(blink::TimeRanges::Range);
 
 #endif // TimeRanges_h