metrics: Fix permissions error on vmlog dir. The default permissions on this log directory were too restrictive (0700, owned by root), and chrome://system and feedback reports are unable to read this data. This relaxes the permissions so that other users can read this information (there's nothing sensitive in here, so it should be fine). BUG=chromium:739490 TEST=Deploy, Checked directory perms and chrome://system Change-Id: Ib0eaa40dba8aa87cd05657b14651595f5ef0e3c0 Reviewed-on: https://chromium-review.googlesource.com/560073 Commit-Ready: Justin TerAvest <[email protected]> Tested-by: Justin TerAvest <[email protected]> Reviewed-by: Dan Erat <[email protected]> Reviewed-by: Justin TerAvest <[email protected]> (cherry picked from commit 2dd3b80efb331f1f4fcc8095e968df8e7616396f) Reviewed-on: https://chromium-review.googlesource.com/571080 Commit-Queue: Bernie Thompson <[email protected]> Tested-by: Bernie Thompson <[email protected]>