Change flag for PowerManagerClient (Take 2)
Replace the generic --enable-stub-interactive with a power manager
specific --power-stub flag.
This was separated out of an earlier CL that became network specific.
Original CL: https://codereview.chromium.org/
189623002
Added paranoia checks (all trybot tests have passed)
BUG=350170
TBR=derat@chromium.org, jennyz@chromium.org
Review URL: https://codereview.chromium.org/
199283003
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@258030 0039d316-1c4b-4281-b951-d872f2087c98