Add cast_crash and cast_shell unittests to chromium.linux.json.

Add cast_crash and cast_shell unittests to chromium.linux.json.

Also correct and update entries in ninja_to_gn.pyl.

BUG=

Committed: https://crrev.com/0f4b5381f94299714d92a23ff6b3953cb122dcf3
Cr-Commit-Position: refs/heads/master@{#336812}

[slan, 2015-06-30 00:07:09]

slan@chromium.org changed reviewers:
+ dpranke@chromium.org, gunsch@chromium.org

[gunsch, 2015-06-30 00:13:18]

lgtm from chromecast perspective

[Dirk Pranke, 2015-06-30 16:35:35]

lgtm, thanks!

[slan, 2015-06-30 16:39:11]

The CQ bit was checked by slan@chromium.org

[commit-bot: I haz the power, 2015-06-30 16:39:20]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1214973003/1

[commit-bot: I haz the power, 2015-06-30 17:45:50]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-06-30 17:46:46]

Patchset 1 (id:??) landed as
https://crrev.com/0f4b5381f94299714d92a23ff6b3953cb122dcf3
Cr-Commit-Position: refs/heads/master@{#336812}