Add crash_handler to all.gyp for WebRTC build target.

Add crash_handler to all.gyp for WebRTC build target.

In revision span 200066:200103 some GYP files have changed
so that the crash_handler target is no longer built as a part
of our chromium_builder_webrtc target.

To be able to use it on Windows testers, add it explicitly.

TEST=local build on Windows.
BUG=none

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=201378

[kjellander_chromium, 2013-05-21 08:04:16]

Examples of failures: http://build.chromium.org/p/chromium.webrtc/waterfall

[kjellander_chromium, 2013-05-21 08:04:17]

Examples of failures: http://build.chromium.org/p/chromium.webrtc/waterfall

[phoglund1, 2013-05-21 08:04:53]

lgtm

[phoglund_chromium, 2013-05-21 08:05:27]

lgtm

[commit-bot: I haz the power, 2013-05-21 08:05:52]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kjellander@chromium.org/15521008/1

[commit-bot: I haz the power, 2013-05-21 08:19:08]

Retried try job too often on linux_chromeos_clang for step(s) compile
http://build.chromium.org/p/tryserver.chromium/buildstatus?builder=linux_chro...

[commit-bot: I haz the power, 2013-05-21 18:47:37]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kjellander@chromium.org/15521008/22001

[commit-bot: I haz the power, 2013-05-21 22:41:46]

Change committed as 201378