Componentize conversion of content::FaviconURL to favicon::FaviconURL

Componentize conversion of content::FaviconURL to favicon::FaviconURL

In preparation of componentization of FaviconTabHelper, introduce a
new target //components/favicon/content (as favicon is a layered
component) and move the function to convert from content::FaviconURL
to favicon::FaviconURL there.

BUG=374281
Committed: https://crrev.com/001b10dec2850df49383baaaf2c401125b10abda
Cr-Commit-Position: refs/heads/master@{#321606}

[sdefresne, 2015-03-20 13:25:03]

sdefresne@chromium.org changed reviewers:
+ avi@chromium.org, jif@chromium.org, thakis@chromium.org

[sdefresne, 2015-03-20 13:25:04]

jif: please take a look

thakis: OWNERS for
  chrome/browser/BUILD.gn

avi: OWNERS for new dependency on content/public

Missing LGTM from OWNERS of dependencies added to DEPS:
    '+content/public',

[Avi (use Gerrit), 2015-03-20 13:51:53]

lgtm

[jif, 2015-03-20 14:08:01]

lgtm

[Nico, 2015-03-20 14:36:50]

lgtm

[sdefresne, 2015-03-20 17:06:54]

The CQ bit was checked by sdefresne@chromium.org

[commit-bot: I haz the power, 2015-03-20 17:07:14]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1020213002/1

[commit-bot: I haz the power, 2015-03-20 18:41:56]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-03-20 18:46:20]

Patchset 1 (id:??) landed as
https://crrev.com/001b10dec2850df49383baaaf2c401125b10abda
Cr-Commit-Position: refs/heads/master@{#321606}