RSS feed support (part 1), 2nd attempt

RSS feed support (part 1), 2nd attempt.

Part 1 is RSS feed auto-discovery.

This will parse the web page header to find the
feeds in the document and notify the browser to
display the RSS icon in the toolbar. You can
click on the icon, but it will just navigate to
the first feed on the page, which (unless it has
been designed to be browser friendly) will just
dump XML as text on the user.

For this reason I have disabled the code that
makes the RSS icon appear and intend to enable 
it when we have a good landing page to display
the XML.


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=11672

[Finnur, 2009-03-13 20:58:27]

Same patch as before (previously reviewed as
http://codereview.chromium.org/43109), except with 4 lines changed in
web_contents.cc that should make the ui tests happier. I ran  all unit-, ui- and
interactive-ui_tests and they all passed.

Original message:

This changelist is the culmination of a patch from an external contributor
(Jorat), our existing code that we took out and new code from me.

This changelist has been lingering in my local tree while we have been putting
all our effort in the effort stabilize the trunk and I'm getting so tired of
fixing the bitrot as people move things around. I think this is also a good time
to checkpoint since the first part of this effort is working (detecting RSS
feeds on the page).

[Evan Martin, 2009-03-13 21:45:43]

LGTM rubber stamp based on last review and discussion of minor tweak via chat :)