Add a gyp variable to indicate additional native libraries to be included in the APK

Add a gyp variable to indicate additional native libraries to be included in the APK

Based on a patch by Chris Hopman <cjhopman@chromium.org>;. This
patch allows us to lazily load libosmesa.so only when it's
needed for content_shell, rather than directly linking it.
https://codereview.chromium.org/23868030/

BUG=

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=224424

[Peter Beverloo, 2013-09-19 14:30:24]

+Chris for review, bulach for second-eyes.

[bulach, 2013-09-19 17:31:34]

lgtm, thanks for the extra info!

[cjhopman, 2013-09-19 18:23:29]

lgtm

[commit-bot: I haz the power, 2013-09-20 12:24:56]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/peter@chromium.org/24253005/1

[commit-bot: I haz the power, 2013-09-20 16:28:52]

Retried try job too often on win_rel for step(s) sync_integration_tests
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=win_rel&nu...

[commit-bot: I haz the power, 2013-09-20 16:31:04]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/peter@chromium.org/24253005/1

[commit-bot: I haz the power, 2013-09-20 17:44:45]

Change committed as 224424