[test] Refactor call-tester to use c-signature.h.

[test] Refactor call-tester to use c-signature.h.

R=mstarzinger@chromium.org
BUG=

Committed: https://crrev.com/2c3e35120f245ec1f116842f475116478317d1d5
Cr-Commit-Position: refs/heads/master@{#28763}

[Michael Starzinger, 2015-06-02 11:45:04]

LGTM.

[titzer, 2015-06-02 14:59:17]

The CQ bit was checked by titzer@chromium.org

[titzer, 2015-06-02 14:59:17]

The patchset sent to the CQ was uploaded after l-g-t-m from
mstarzinger@chromium.org
Link to the patchset: https://codereview.chromium.org/1146173005/#ps40001
(title: " ")

[commit-bot: I haz the power, 2015-06-02 14:59:29]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1146173005/40001

[commit-bot: I haz the power, 2015-06-02 15:01:00]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2015-06-02 15:01:15]

Patchset 3 (id:??) landed as
https://crrev.com/2c3e35120f245ec1f116842f475116478317d1d5
Cr-Commit-Position: refs/heads/master@{#28763}