Disk cache: Re-initialize stats counters if they are zero on-disk.

Disk cache: Re-initialize stats counters if they are zero on-disk.

Stats are saved to disk every five minutes. If a client is initializing
the cache, and it crashes before saving the stats for the first time,
the next run will see an empty stats storage, and will discard the cache
because it may indicate that the storage address was invalid.

Now, we check the contents to see if the storage was empty and re-initialize
things as needed.

BUG=none
TEST=net_unittests

Committed: https://crrev.com/4f2eab7cd613d87c79a192bfc5183f79483d95bf
Cr-Commit-Position: refs/heads/master@{#319204}

[rvargas (doing something else), 2015-03-05 00:57:27]

rvargas@chromium.org changed reviewers:
+ rtenneti@chromium.org

[ramant (doing other things), 2015-03-05 01:09:35]

lgtm

https://codereview.chromium.org/980003002/diff/1/net/disk_cache/blockfile/sta...
File net/disk_cache/blockfile/stats.cc (right):

https://codereview.chromium.org/980003002/diff/1/net/disk_cache/blockfile/sta...
net/disk_cache/blockfile/stats.cc:115: // The sorage is empty which means that
SerializeStats() was never
nit: sorage -> storage?

[rvargas (doing something else), 2015-03-05 02:23:50]

Thanks!

https://codereview.chromium.org/980003002/diff/1/net/disk_cache/blockfile/sta...
File net/disk_cache/blockfile/stats.cc (right):

https://codereview.chromium.org/980003002/diff/1/net/disk_cache/blockfile/sta...
net/disk_cache/blockfile/stats.cc:115: // The sorage is empty which means that
SerializeStats() was never
On 2015/03/05 01:09:35, ramant wrote:
> nit: sorage -> storage?

Done.

[rvargas (doing something else), 2015-03-05 02:23:56]

The CQ bit was checked by rvargas@chromium.org

[rvargas (doing something else), 2015-03-05 02:23:57]

The patchset sent to the CQ was uploaded after l-g-t-m from
rtenneti@chromium.org
Link to the patchset: https://codereview.chromium.org/980003002/#ps20001 (title:
"Fix typo")

[commit-bot: I haz the power, 2015-03-05 02:25:03]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/980003002/20001

[commit-bot: I haz the power, 2015-03-05 03:35:19]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-05 03:36:03]

Patchset 2 (id:??) landed as
https://crrev.com/4f2eab7cd613d87c79a192bfc5183f79483d95bf
Cr-Commit-Position: refs/heads/master@{#319204}