chromium: Update all channels to latest versions.

With this commit, the following new upstream versions are introduced:

stable: 36.0.1985.125 -> 37.0.2062.94
beta:   37.0.2062.58  -> 37.0.2062.94
dev:    38.0.2107.3   -> 38.0.2125.8

All channels built fine on my machine and were tested against a few
sites.

Stable and beta channel now contain the same release, because version
37 hit the stable channel. For release notes, please have a look at the
announcement:

http://googlechromereleases.blogspot.de/2014/08/stable-channel-update_26.html



Of course we're also dropping all version 36 specific crap, such as the
architecture-specific target suffix for builds, which now is no longer
needed.

The gyp flag use_mojo=0 is no longer needed, as it was a workaround
concerning version 37.0.2054.3 only.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>