Remove |using base::StringPiece| from net/spdy header files.

Remove |using base::StringPiece| from net/spdy header files.

|using| directives should not be global, but they should be used on a per-file bases.  Therefore they should not be placed in header files.

Committed: https://crrev.com/27114889b608254dab9266fbcae805714c707c13
Cr-Commit-Position: refs/heads/master@{#361378}

[Bence, 2015-11-19 20:28:36]

Description was changed from

==========
Remove |using base::StringPiece| from net/spdy header files.
==========

to

==========
Remove |using base::StringPiece| from net/spdy header files.

|using| directives should not be global, but they should be used on a per-file
bases.  Therefore they should not be placed in header files.
==========

[Bence, 2015-11-19 20:29:47]

bnc@chromium.org changed reviewers:
+ ttuttle@chromium.org

[Bence, 2015-11-19 20:29:47]

ttuttle@: PTAL.  Thanks.

[Deprecated (see juliatuttle), 2015-11-24 15:30:38]

lgtm.

[Bence, 2015-11-24 15:34:05]

The CQ bit was checked by bnc@chromium.org

[commit-bot: I haz the power, 2015-11-24 15:34:51]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1458163002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1458163002/1

[commit-bot: I haz the power, 2015-11-24 17:16:12]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-11-24 17:17:17]

Patchset 1 (id:??) landed as
https://crrev.com/27114889b608254dab9266fbcae805714c707c13
Cr-Commit-Position: refs/heads/master@{#361378}