bpf_dsl: Move {Bool,Result}ExprImpl definition into separate header

bpf_dsl: Move {Bool,Result}ExprImpl definition into separate header

Now that "extern template class scoped_refptr<Opaque>" is supported,
we no longer need to expose the class definitions for BoolExprImpl and
ResultExprImpl to end users.

BUG=414363
Committed: https://crrev.com/fb10cce5ca304e0ed40290c7dd2deaf303a7aecd
Cr-Commit-Position: refs/heads/master@{#299507}

[mdempsky, 2014-10-14 01:25:19]

mdempsky@chromium.org changed reviewers:
+ leecam@chromium.org

[leecam, 2014-10-14 01:38:11]

lgtm

[mdempsky, 2014-10-14 01:50:25]

The CQ bit was checked by mdempsky@chromium.org

[commit-bot: I haz the power, 2014-10-14 01:50:44]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/635223006/1

[commit-bot: I haz the power, 2014-10-14 01:50:46]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-10-14 01:50:46]

No LGTM from a valid reviewer yet. Only full committers are accepted.
Even if an LGTM may have been provided, it was from a non-committer or
a provisional committer, _not_ a full super star committer.
See http://www.chromium.org/getting-involved/become-a-committer
Note that this has nothing to do with OWNERS files.

[mdempsky, 2014-10-14 01:54:55]

mdempsky@chromium.org changed reviewers:
+ jorgelo@chromium.org

[mdempsky, 2014-10-14 01:54:55]

jorgelo: PTAL

[Jorge Lucangeli Obes, 2014-10-14 15:51:06]

lgtm

[mdempsky, 2014-10-14 17:27:10]

The CQ bit was checked by mdempsky@chromium.org

[commit-bot: I haz the power, 2014-10-14 17:27:48]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/635223006/1

[commit-bot: I haz the power, 2014-10-14 17:57:07]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2014-10-14 17:58:07]

Patchset 1 (id:??) landed as
https://crrev.com/fb10cce5ca304e0ed40290c7dd2deaf303a7aecd
Cr-Commit-Position: refs/heads/master@{#299507}