fully cache small audio/video

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/location.h"
 #include "base/single_thread_task_runner.h"
@@ skipping 131 matching lines @@
   return true;
 }
 
 void UrlData::OnEmpty() {
   DCHECK(thread_checker_.CalledOnValidThread());
   base::ThreadTaskRunnerHandle::Get()->PostTask(
       FROM_HERE, base::Bind(&UrlIndex::RemoveUrlDataIfEmpty, url_index_,
                             scoped_refptr<UrlData>(this)));
 }
 
-bool UrlData::Valid() const {
+bool UrlData::FullyCached() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  if (length_ == kPositionNotSpecified)
+    return false;
+  // Check that the first unavailable block in the cache is after the
+  // end of the file.
+  return (multibuffer()->FindNextUnavailable(0) << kBlockSizeShift) >= length_;
+}
+
+bool UrlData::Valid() {
   DCHECK(thread_checker_.CalledOnValidThread());
   base::Time now = base::Time::Now();
-  if (!range_supported_)
+  if (!range_supported_ && !FullyCached())
     return false;
   // When ranges are not supported, we cannot re-use cached data.
   if (valid_until_ > now)
     return true;
   if (now - last_used_ <
       base::TimeDelta::FromSeconds(kUrlMappingTimeoutSeconds))
     return true;
   return false;
 }
 
@@ skipping 103 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