Add owners to [webrtc,talk]/build and *.isolate (take 2)

After fischman@'s comments in http://review.webrtc.org/2347006/ here's another CL to clean up the redundancies and add wu@ to webrtc/build/

TEST=none
BUG=none
R=andrew@webrtc.org, fischman@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/2348006

git-svn-id: http://webrtc.googlecode.com/svn/trunk/talk@4928 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/OWNERS b/OWNERS
index b55b3a3..ddb55cf 100644
--- a/OWNERS
+++ b/OWNERS
@@ -7,4 +7,6 @@
 perkj@webrtc.org
 sergeyu@chromium.org
 tommi@webrtc.org
-wu@webrtc.org
\ No newline at end of file
+wu@webrtc.org
+per-file *.isolate=kjellander@webrtc.org
+