media: Add UMA stats for bytes going in and out of multibuffer 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/location.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/single_thread_task_runner.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "media/blink/resource_multibuffer_data_provider.h"
 #include "media/blink/url_index.h"
 
 namespace media {
 
 const int kBlockSizeShift = 15;  // 1<<15 == 32kb
 const int kUrlMappingTimeoutSeconds = 300;
@@ skipping 27 matching lines @@
       have_data_origin_(false),
       cors_mode_(cors_mode),
       url_index_(url_index),
       length_(kPositionNotSpecified),
       range_supported_(false),
       cacheable_(false),
       last_used_(),
       multibuffer_(this, url_index_->block_shift_),
       frame_(url_index->frame()) {}
 
-UrlData::~UrlData() {}
+UrlData::~UrlData() {
+  UMA_HISTOGRAM_MEMORY_KB("Media.BytesReadFromCache",
+                          BytesReadFromCache() >> 10);
+  UMA_HISTOGRAM_MEMORY_KB("Media.BytesReadFromNetwork",
+                          BytesReadFromNetwork() >> 10);
+}
 
 std::pair<GURL, UrlData::CORSMode> UrlData::key() const {
   DCHECK(thread_checker_.CalledOnValidThread());
   return std::make_pair(url(), cors_mode());
 }
 
 void UrlData::set_valid_until(base::Time valid_until) {
   DCHECK(thread_checker_.CalledOnValidThread());
   valid_until_ = valid_until;
 }
@@ skipping 211 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