Implement cache counting for the simple and memory backends.

net/disk_cache/simple/simple_backend_impl.cc

 // Copyright (c) 2013 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/simple/simple_backend_impl.h"
 
 #include <algorithm>
 #include <cstdlib>
 #include <functional>
 
@@ skipping 452 matching lines @@
       base::Bind(&SimpleBackendImpl::IndexReadyForDoom, AsWeakPtr(),
                  initial_time, end_time, callback));
 }
 
 int SimpleBackendImpl::DoomEntriesSince(
     const Time initial_time,
     const CompletionCallback& callback) {
   return DoomEntriesBetween(initial_time, Time(), callback);
 }
 
+void SimpleBackendImpl::IndexReadyForCalculation(

[gavinp, 2015/10/13 15:50:12]

Isn't this an ordering violation? See
https://google-styleguide.googlecode.com/svn/trunk/cppguide.html#Declaration_...

[msramek, 2015/10/13 17:25:50]

Yep. I tried to follow IndexReadyForDoom, but that one was already misplaced.

+    const CompletionCallback& callback,
+    int result) {
+  if (result == net::OK)
+    result = static_cast<int>(index_->GetCacheSize());
+  callback.Run(result);
+}
+
 int SimpleBackendImpl::CalculateSizeOfAllEntries(
     const CompletionCallback& callback) {
-  // TODO(msramek): Implement.
-  return net::ERR_NOT_IMPLEMENTED;
+  return index_->ExecuteWhenReady(
+      base::Bind(&SimpleBackendImpl::IndexReadyForCalculation,
+                 AsWeakPtr(),
+                 callback));

[gavinp, 2015/10/13 15:50:12]

Did git cl format not join these lines? Weird...

[msramek, 2015/10/13 17:25:50]

Ehm, I didn't run it.

[gavinp, 2015/10/14 15:08:06]

We're very diligent about that in net/. Generally if you're not going to run it,
please file a bug against git cl format (I believe tag is Build-Tools) for the
specific problem you're working around.

[msramek, 2015/10/14 16:11:58]

Acknowledged.

 }
 
 class SimpleBackendImpl::SimpleIterator final : public Iterator {
  public:
   explicit SimpleIterator(base::WeakPtr<SimpleBackendImpl> backend)
       : backend_(backend),
         weak_factory_(this) {
   }
 
   // From Backend::Iterator:
@@ skipping 252 matching lines @@
 }
 
 // static
 void SimpleBackendImpl::FlushWorkerPoolForTesting() {
   // We only need to do this if we there is an active task runner.
   if (base::ThreadTaskRunnerHandle::IsSet())
     g_sequenced_worker_pool.Get().FlushForTesting();
 }
 
 }  // namespace disk_cache