Fix ChunkDemuxer so it properly outputs buffered ranges.

media/base/ranges.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_RANGES_H_
 #define MEDIA_BASE_RANGES_H_
 
+#include <algorithm>
 #include <ostream>
 #include <vector>
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "media/base/media_export.h"
 
 namespace media {
 
 // Ranges allows holding an ordered list of ranges of [start,end) intervals.
@@ skipping 11 matching lines @@
   // Return the number of disjoint ranges.
   size_t size() const;
 
   // Return the "i"'th range's start & end (0-based).
   T start(int i) const;
   T end(int i) const;
 
   // Clear all ranges.
   void clear();
 
+  // Computes the intersection between this range and |other|.
+  Ranges<T> IntersectionWith(const Ranges<T>& other);
+
  private:
   // Disjoint, in increasing order of start.
   std::vector<std::pair<T, T> > ranges_;
 };
 
 //////////////////////////////////////////////////////////////////////
 // EVERYTHING BELOW HERE IS IMPLEMENTATION DETAIL!!
 //////////////////////////////////////////////////////////////////////
 
 template<class T>
@@ skipping 59 matching lines @@
 template<class T>
 T Ranges<T>::end(int i) const {
   return ranges_[i].second;
 }
 
 template<class T>
 void Ranges<T>::clear() {
   ranges_.clear();
 }
 
+template<class T>
+Ranges<T> Ranges<T>::IntersectionWith(const Ranges<T>& other) {
+  Ranges<T> result;
+
+  size_t i = 0;
+  size_t j = 0;
+
+  while (i < size() && j < other.size()) {
+    T max_start = std::max(start(i), other.start(j));
+    T min_end = std::min(end(i), other.end(j));
+
+    // Add an intersection range to the result if the ranges overlap.
+    if (max_start < min_end)
+      result.Add(max_start, min_end);
+
+    if (end(i) < other.end(j))
+      ++i;
+    else
+      ++j;
+  }
+
+  return result;
+}
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_RANGES_H_