Add cld2_table_size variable to GN build.

Add cld2_table_size variable to GN build.

This variable has been in common.gypi for some time, but was missing from GN.

BUG=528257
Committed: https://crrev.com/b32a1daf9763b66e7f12a3e88e4b526589dd8479
Cr-Commit-Position: refs/heads/master@{#347576}

[andrewhayden, 2015-09-05 11:57:56]

andrewhayden@google.com changed reviewers:
+ jbudorick@chromium.org

[andrewhayden, 2015-09-05 11:58:35]

andrewhayden@google.com changed reviewers:
+ andrewhayden@google.com, droger@chromium.org

[andrewhayden, 2015-09-05 11:58:35]

PTAL. Followup from https://codereview.chromium.org/1327543003

[jbudorick, 2015-09-05 16:41:16]

lgtm

[andrewhayden, 2015-09-05 20:09:14]

The CQ bit was checked by andrewhayden@google.com

[commit-bot: I haz the power, 2015-09-05 20:09:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1306053014/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1306053014/1

[commit-bot: I haz the power, 2015-09-05 20:58:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-05 20:59:27]

Patchset 1 (id:??) landed as
https://crrev.com/b32a1daf9763b66e7f12a3e88e4b526589dd8479
Cr-Commit-Position: refs/heads/master@{#347576}