Add an whitelist for calling GN's exec_script.

Add an whitelist for calling GN's exec_script.

This will be used in Chrome to limit new callers and force root owners reviews for new uses of exec_script.

This deletes the CommonSetup and DependentSetup class. Only the Setup class is used now. This was added to support generating .gyp files where there were many similar builds, but this functionality hasn't been used for ~1 year.

Committed: https://crrev.com/4d305869607ee5ffff4df2caaa8ca2381e029193
Cr-Commit-Position: refs/heads/master@{#319517}

[brettw, 2015-03-05 23:39:17]

brettw@chromium.org changed reviewers:
+ scottmg@chromium.org

[scottmg, 2015-03-06 21:42:56]

lgtm

[brettw, 2015-03-06 21:44:05]

The CQ bit was checked by brettw@chromium.org

[commit-bot: I haz the power, 2015-03-06 21:44:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/988563002/20001

[scottmg, 2015-03-06 21:45:15]

Could you add a small test for this?

[commit-bot: I haz the power, 2015-03-06 22:38:30]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-03-06 22:39:11]

Patchset 2 (id:??) landed as
https://crrev.com/4d305869607ee5ffff4df2caaa8ca2381e029193
Cr-Commit-Position: refs/heads/master@{#319517}