trunk-tracking: update to r3402

Adjust for fetchers and options that moved from apache/ to system/ in r3390.

Use AllocateFetcher() hook from r3402 to put the native fetcher into the fetcher
map maintained by the SystemRewriteDriverFactory.
Merge pull request #480 from pagespeed/jefftk-update-trunk-tracking

Adjust for fetchers and options that moved from apache/ to system/ in r3390