Lazily prune the multibuffer block cache.

media/blink/url_index.cc

 // 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.
 
 #include <set>
 #include <utility>
 
 #include "base/bind.h"
 #include "base/message_loop/message_loop.h"
 #include "base/time/time.h"
@@ skipping 150 matching lines @@
 
 size_t UrlData::CachedSize() {
   DCHECK(thread_checker_.CalledOnValidThread());
   return multibuffer()->map().size();
 }
 
 UrlIndex::UrlIndex(blink::WebFrame* frame) : UrlIndex(frame, kBlockSizeShift) {}
 
 UrlIndex::UrlIndex(blink::WebFrame* frame, int block_shift)
     : frame_(frame),
-      lru_(new MultiBuffer::GlobalLRU()),
+      lru_(new MultiBuffer::GlobalLRU(
+          base::MessageLoop::current()->task_runner())),
       block_shift_(block_shift),
       weak_factory_(this) {}
 
 UrlIndex::~UrlIndex() {}
 
 void UrlIndex::RemoveUrlDataIfEmpty(const scoped_refptr<UrlData>& url_data) {
   if (!url_data->multibuffer()->map().empty())
     return;
 
   auto i = by_url_.find(url_data->key());
@@ skipping 46 matching lines @@
          url_data->CachedSize() > (*by_url_slot)->CachedSize())) {
       *by_url_slot = url_data;
     } else {
       (*by_url_slot)->MergeFrom(url_data);
     }
   }
   return *by_url_slot;
 }
 
 }  // namespace media