Fixes possible deadlock in fontservice

Fixes possible deadlock in fontservice

Here's the sequence:
1. FontServiceThread::OpenStreamImpl
2. FontService::OpenStream
3. FontServiceThread::OnOpenStreamComplete

If between 2 and 3 FontService gets a connection error the callback
that calls OnOpenStreamComplete is never received, and the thread that
called OpenStream() is stuck forever.

Fix is to add the WaitableEvents to a member variable and if a
connection error is received all WaitableEvents are signaled.

BUG=594600
TEST=none
R=erg@chromium.org

Committed: https://crrev.com/b8d418d3c26048ed54ce7039bcc4c627a6804c54
Cr-Commit-Position: refs/heads/master@{#389515}

[Elliot Glaysher, 2016-04-25 18:15:10]

lgtm

[sky, 2016-04-25 18:20:31]

The CQ bit was checked by sky@chromium.org

[commit-bot: I haz the power, 2016-04-25 18:20:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1916003002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1916003002/1

[commit-bot: I haz the power, 2016-04-25 18:26:12]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-25 18:28:15]

Description was changed from

==========
Fixes possible deadlock in fontservice

Here's the sequence:
1. FontServiceThread::OpenStreamImpl
2. FontService::OpenStream
3. FontServiceThread::OnOpenStreamComplete

If between 2 and 3 FontService gets a connection error the callback
that calls OnOpenStreamComplete is never received, and the thread that
called OpenStream() is stuck forever.

Fix is to add the WaitableEvents to a member variable and if a
connection error is received all WaitableEvents are signaled.

BUG=594600
TEST=none
R=erg@chromium.org
==========

to

==========
Fixes possible deadlock in fontservice

Here's the sequence:
1. FontServiceThread::OpenStreamImpl
2. FontService::OpenStream
3. FontServiceThread::OnOpenStreamComplete

If between 2 and 3 FontService gets a connection error the callback
that calls OnOpenStreamComplete is never received, and the thread that
called OpenStream() is stuck forever.

Fix is to add the WaitableEvents to a member variable and if a
connection error is received all WaitableEvents are signaled.

BUG=594600
TEST=none
R=erg@chromium.org

Committed: https://crrev.com/b8d418d3c26048ed54ce7039bcc4c627a6804c54
Cr-Commit-Position: refs/heads/master@{#389515}
==========

[commit-bot: I haz the power, 2016-04-25 18:28:16]

Patchset 1 (id:??) landed as
https://crrev.com/b8d418d3c26048ed54ce7039bcc4c627a6804c54
Cr-Commit-Position: refs/heads/master@{#389515}