DEPS.xwalk: Roll v8-crosswalk (390bd33 -> 03d8b6c)

03d8b6c Merge pull request #55 from elvin-nnov/master
66b6f26 XDK heap profiler collector
Merge pull request #2552 from elvin-nnov/master

Updated the revision to v8 for supporting of in-depth allocation tracker profiler