The machine types were incorrect for the runtime function and argument
count parameters. The latter was introduced in 3e2085eb, while the
former seems to always have been wrong.

This was not an issue so far because GetRuntimeCallDescriptor was only
called after the representation selection phase and thus the machine
type was ignored.

R=jarin@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2250863004
Cr-Commit-Position: refs/heads/master@{#38720}