Fix a memory leak in BrowsingDataFilterBuilder

Fix a memory leak in BrowsingDataFilterBuilder

BrowsingDataFilterBuilder is an abstract class that has a non-virtual
destructor. This is a mistake - since the class and its subclasses are
non-copyable, they're typically handled by pointers; calling delete on
such a pointer will only call the base class destructor, not those of
the subclasses, and thus leak any attributes of the subclasses.

This was spotted by ASan in the context of the CL implementing the task
scheduler for BrowsingDataRemover. When a task was finished processing,
its destructor did not correctly destroy the contained
BrowsingDataFilterBuilder.

BUG=630327
Committed: https://crrev.com/09df8fd82d462a314bde355b8aba7a221f1f3bbc
Cr-Commit-Position: refs/heads/master@{#407765}

[msramek, 2016-07-26 09:56:46]

The CQ bit was checked by msramek@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-07-26 09:57:00]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[msramek, 2016-07-26 09:58:13]

msramek@chromium.org changed reviewers:
+ vabr@chromium.org

[msramek, 2016-07-26 09:58:14]

Hi Václav,

Can I ask you for a quick context-free review?

Thanks,
Martin

[vabr (Chromium), 2016-07-26 10:05:02]

LGTM, nice catch!
Vaclav

[msramek, 2016-07-26 10:42:45]

The CQ bit was unchecked by msramek@chromium.org

[msramek, 2016-07-26 10:42:48]

The CQ bit was checked by msramek@chromium.org

[commit-bot: I haz the power, 2016-07-26 10:43:02]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-07-26 11:10:33]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-07-26 11:12:40]

Description was changed from

==========
Fix a memory leak in BrowsingDataFilterBuilder

BrowsingDataFilterBuilder is an abstract class that has a non-virtual
destructor. This is a mistake - since the class and its subclasses are
non-copyable, they're typically handled by pointers; calling delete on
such a pointer will only call the base class destructor, not those of
the subclasses, and thus leak any attributes of the subclasses.

This was spotted by ASan in the context of the CL implementing the task
scheduler for BrowsingDataRemover. When a task was finished processing,
its destructor did not correctly destroy the contained
BrowsingDataFilterBuilder.

BUG=630327
==========

to

==========
Fix a memory leak in BrowsingDataFilterBuilder

BrowsingDataFilterBuilder is an abstract class that has a non-virtual
destructor. This is a mistake - since the class and its subclasses are
non-copyable, they're typically handled by pointers; calling delete on
such a pointer will only call the base class destructor, not those of
the subclasses, and thus leak any attributes of the subclasses.

This was spotted by ASan in the context of the CL implementing the task
scheduler for BrowsingDataRemover. When a task was finished processing,
its destructor did not correctly destroy the contained
BrowsingDataFilterBuilder.

BUG=630327

Committed: https://crrev.com/09df8fd82d462a314bde355b8aba7a221f1f3bbc
Cr-Commit-Position: refs/heads/master@{#407765}
==========

[commit-bot: I haz the power, 2016-07-26 11:12:41]

Patchset 1 (id:??) landed as
https://crrev.com/09df8fd82d462a314bde355b8aba7a221f1f3bbc
Cr-Commit-Position: refs/heads/master@{#407765}