Calculate the size of all cache entries between two points in time.

net/disk_cache/blockfile/backend_impl.cc

Index: net/disk_cache/blockfile/backend_impl.cc
diff --git a/net/disk_cache/blockfile/backend_impl.cc b/net/disk_cache/blockfile/backend_impl.cc
index f0cdb0c9048fbd964cd11769fcc0ce6514a1418a..e9371813aa13bffe069ffba6cfd87a558255ad8a 100644
--- a/net/disk_cache/blockfile/backend_impl.cc
+++ b/net/disk_cache/blockfile/backend_impl.cc
@@ -1270,6 +1270,15 @@ int BackendImpl::CalculateSizeOfAllEntries(const CompletionCallback& callback) {
   return net::ERR_IO_PENDING;
 }
 
+int BackendImpl::CalculateSizeOfEntriesBetween(
+    base::Time initial_time,
+    base::Time end_time,
+    const CompletionCallback& callback) {
+  // Calculating the size of a subset of cache entries is not implemented
+  // because it would require to open and read all entries from disk.
+  return net::ERR_NOT_IMPLEMENTED;

[gavinp, 2017/01/12 16:07:35]

Why not move all of these ERR_NOT_IMPLEMENTED versions up into the
disk_cache::Backend directly? Seems more logical than repeating this over and
over again.

+}
+
 class BackendImpl::IteratorImpl : public Backend::Iterator {
  public:
   explicit IteratorImpl(base::WeakPtr<InFlightBackendIO> background_queue)