Track SimpleCache memory usage in net/ MemoryDumpProvider

net/disk_cache/simple/simple_backend_impl.cc

Index: net/disk_cache/simple/simple_backend_impl.cc
diff --git a/net/disk_cache/simple/simple_backend_impl.cc b/net/disk_cache/simple/simple_backend_impl.cc
index e5645e357ebd44aecac4b580e3fb88444f7dc7b9..e8a38acbabee14cd53af6e8dab0b93b847e604f5 100644
--- a/net/disk_cache/simple/simple_backend_impl.cc
+++ b/net/disk_cache/simple/simple_backend_impl.cc
@@ -30,6 +30,7 @@
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
+#include "base/trace_event/memory_usage_estimator.h"
 #include "net/base/net_errors.h"
 #include "net/disk_cache/cache_util.h"
 #include "net/disk_cache/simple/simple_entry_format.h"
@@ -552,6 +553,11 @@ void SimpleBackendImpl::OnExternalCacheHit(const std::string& key) {
   index_->UseIfExists(simple_util::GetEntryHashKey(key));
 }
 
+size_t SimpleBackendImpl::EstimateMemoryUsage() const {
+  return base::trace_event::EstimateMemoryUsage(index_) +
+         base::trace_event::EstimateMemoryUsage(active_entries_);
+}
+
 void SimpleBackendImpl::InitializeIndex(const CompletionCallback& callback,
                                         const DiskStatResult& result) {
   if (result.net_error == net::OK) {