Add HttpCache histograms focussed on blocking and transaction type.

net/disk_cache/mem_backend_impl.cc

 // 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.
 
 #include "net/disk_cache/mem_backend_impl.h"
 
 #include "base/logging.h"
 #include "base/sys_info.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/cache_util.h"
@@ skipping 106 matching lines @@
 }
 
 void MemBackendImpl::InsertIntoRankingList(MemEntryImpl* entry) {
   rankings_.Insert(entry);
 }
 
 void MemBackendImpl::RemoveFromRankingList(MemEntryImpl* entry) {
   rankings_.Remove(entry);
 }
 
+net::CacheType MemBackendImpl::GetCacheType() const {
+  return net::MEMORY_CACHE;
+}
+
 int32 MemBackendImpl::GetEntryCount() const {
   return static_cast<int32>(entries_.size());
 }
 
 int MemBackendImpl::OpenEntry(const std::string& key, Entry** entry,
                               const CompletionCallback& callback) {
   if (OpenEntry(key, entry))
     return net::OK;
 
   return net::ERR_FAILED;
@@ skipping 181 matching lines @@
   if (current_size_ > max_size_)
     TrimCache(false);
 }
 
 void MemBackendImpl::SubstractStorageSize(int32 bytes) {
   current_size_ -= bytes;
   DCHECK_GE(current_size_, 0);
 }
 
 }  // namespace disk_cache