Revert 51231 - Loosen permission on extension temp dir when a flag is used....

Revert 51231 - Loosen permission on extension temp dir when a flag is used.

Issue 35198 can not be reproduced locally.  To enable users to do experiments, three command line flags are added to chrome:

--issue35198-crxdir-browser: Have the browser process create the directory in which the extension will be unzipped.

--issue35198-logging: Enable log messages from directory creation in the utility process to be moved to the browser process.

--issue35198-permission: Use the most permissive file permissions possible on the extension unpack directory.

BUG=35198
TEST=manual

Review URL: http://codereview.chromium.org/2802018

TBR=skerner@chromium.org

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=51238