Re-add forced cachedir creation.
Re-add forced cachedir creation.

In CL:33875, we added caching; that caching specifically forced
the cache dir to be created before trying any upgrades... that
code was -1'd out however.

Turns out, it was needed; if this is the first run and no cache-dir
exists, but an upgrade is necessary, it would fail.

BUG=chromium-os:34450
TEST=manual, harass vapier to test it in addition.

Change-Id: I44ff2c80f832b8e72a48f4131f1d5cfe7c1e3b1b
Reviewed-on: https://gerrit.chromium.org/gerrit/34331
Reviewed-by: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>
Tested-by: Brian Harring <fdc2d0a2e2340b623587cee5ea8dff425d1eb1f3@chromium.org>

zhang0137/chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,chadversary/chromiumos.chromite,coreos/chromite,coreos/chromite,zhang0137/chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,zhang0137/chromite