Updated the revision to v8 which contains bug fixes for XDK Heap Profiler: windows compilation and types handling fix

DEPS.xwalk: Roll v8-crosswalk (5e874a0 -> 8e8223d)

8e8223d Merge pull request #69 from elvin-nnov/crosswalk-10/39.0.2171.62
1dfd904 XDK HeapProfiler bug fixes: object's types
        determination and compilation on Windows
7bc204b XDK: Convert line endings from DOS to Unix.