Fix progress reporting for multibuffers to report progress for every byte we receive.

media/blink/multibuffer.h

 // Copyright 2015 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_BLINK_MULTIBUFFER_H_
 #define MEDIA_BLINK_MULTIBUFFER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 96 matching lines @@
     virtual ~DataProvider() {}
 
     // Returns the block number that is to be returned
     // by the next Read() call.
     virtual MultiBufferBlockId Tell() const = 0;
 
     // Returns true if one (or more) blocks are
     // availble to read.
     virtual bool Available() const = 0;
 
+    // Returns how many bytes are available, note that Available() may still
+    // return false even if AvailableBytes() returns true.

[liberato (no reviews please), 2016/05/13 17:45:54]

s/true./greater than zero, if less than a full block is available./ (?)

[hubbe, 2016/05/13 17:51:36]

Done.

+    virtual int64_t AvailableBytes() const = 0;
+
     // Returns the next block. Only valid if Available()
     // returns true. Last block might be of a smaller size
     // and after the last block we will get an end-of-stream
     // DataBuffer.
     virtual scoped_refptr<DataBuffer> Read() = 0;
 
     // Ask the data provider to stop giving us data.
     // It's ok if the effect is not immediate.
     virtual void SetDeferred(bool deferred) = 0;
   };
@@ skipping 115 matching lines @@
   // Unpin block 4 & 5: PinRange(4, 6, -1);
   void PinRange(const BlockId& from, const BlockId& to, int32_t how_much);
 
   // Calls PinRange for each range in |ranges|, convenience
   // function for applying multiple changes to the pinned ranges.
   void PinRanges(const IntervalMap<BlockId, int32_t>& ranges);
 
   // Increment max cache size by |size| (counted in blocks).
   void IncrementMaxSize(int32_t size);
 
+  // Returns how many bytes have been received by the data providers at position
+  // |block|, which have not yet been submitted to the multibuffer cache.
+  // The returned number should be less than the size of one block.
+  int64_t UncommittedBytesAt(const BlockId& block);
+
   // Caller takes ownership of 'provider', cache will
   // not call it anymore.
   std::unique_ptr<DataProvider> RemoveProvider(DataProvider* provider);
 
   // Add a writer to this cache. Cache takes ownership, and may
   // destroy |provider| later. (Not during this call.)
   void AddProvider(std::unique_ptr<DataProvider> provider);
 
   // Transfer all data from |other| to this.
   void MergeFrom(MultiBuffer* other);
@@ skipping 76 matching lines @@
   // and 0 for all blocks that are not. Used to quickly figure out
   // ranges of available/unavailable blocks without iterating.
   IntervalMap<BlockId, int32_t> present_;
 
   DISALLOW_COPY_AND_ASSIGN(MultiBuffer);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BLINK_MULTIBUFFER_H_