Move IDS_LEARN_MORE to components_strings.grd

Move IDS_LEARN_MORE to components_strings.grd

To componentize sad_tab related code, move IDS_LEARN_MORE to outside of chrome.

BUG=402485
TBR=sky@chromium.org for include fix under chrome/browser

Committed: https://crrev.com/a804d98340be56cb3fa7c8c861dca47e47d1b8d8
Cr-Commit-Position: refs/heads/master@{#292908}

[hashimoto, 2014-09-02 08:40:50]

hashimoto@chromium.org changed reviewers:
+ blundell@chromium.org

[blundell, 2014-09-02 08:43:28]

lgtm

[hashimoto, 2014-09-02 08:52:55]

hashimoto@chromium.org changed reviewers:
+ sky@chromium.org

[hashimoto, 2014-09-02 08:53:08]

TBRing sky@chromium.org for include fix under chrome/browser

[hashimoto, 2014-09-02 08:53:12]

The CQ bit was checked by hashimoto@chromium.org

[commit-bot: I haz the power, 2014-09-02 08:53:35]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/hashimoto@chromium.org/530963002/20001

[hashimoto, 2014-09-02 09:06:08]

The CQ bit was checked by hashimoto@chromium.org

[commit-bot: I haz the power, 2014-09-02 09:06:12]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/hashimoto@chromium.org/530963002/40001

[commit-bot: I haz the power, 2014-09-02 10:01:00]

FYI, CQ is re-trying this CL (attempt #1).
The failing builders are:
  mac_chromium_rel_swarming on tryserver.chromium.mac
(http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[commit-bot: I haz the power, 2014-09-02 10:37:13]

Committed patchset #3 (id:40001) as 7f45c7e3f0e086761620bafa041c0cc05185855d

[commit-bot: I haz the power, 2014-09-10 03:17:59]

Patchset 3 (id:??) landed as
https://crrev.com/a804d98340be56cb3fa7c8c861dca47e47d1b8d8
Cr-Commit-Position: refs/heads/master@{#292908}