Refer to Chrome's DEPS to make rolling easier.

- Sync Chrome's DEPS to chromium_deps/, and use the From() keyword
  to pull the correct revisions from it, rather than having to manually
  enter them.
- This idea is borrowed from the WebKit DEPS:
http://trac.webkit.org/browser/trunk/Source/WebKit/chromium/DEPS
- Fix update.py's DEPS parsing to handle From().
- Roll Chrome 120526:122775.
- Organize the deps alphabetically.
- Sync the in-tree gold linker, which is now required due to a change
  in the linker flags.
- Add the new deps to .gitignore.

BUG=
TEST=build on all platforms

Review URL: https://webrtc-codereview.appspot.com/401004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@1755 4adac7df-926f-26a2-2b94-8c16560cd09d
3 files changed