Linux: make --renderer-startup-dialog work on Linux.
Linux: make --renderer-startup-dialog work on Linux.

This is needed, along with --enable-sandbox-debugging, to debug SUID
sandboxed renderers.

With this patch, one can run:
  ./out/Debug/chrome --enable-sandbox-debugging --renderer-startup-dialog

Then, in GDB, attach to the PID which is printed to stderr and
continue. Then send SIGUSR1 to the PID to resume the renderer.

http://codereview.chromium.org/159211


git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@21303 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser