Revert "Revert "crash-reporter: Don't send ps command lines with crash reporter""

This reverts commit 59d8695734dac2ce70b17d2a58049083e65e997d.

My original commit did not actually break anything, so this just puts it back.

BUG=chromium-os:13576
TEST=unit tests, logging_{UserCrash,CrashSender} autotests

Review URL: http://codereview.chromium.org/6765017

Change-Id: I5b9ebb2b210b86fb4efaf49c71dcd2562805c973