Remove the importedDocument functions from HTML imports classes.

Remove the importedDocument functions from HTML imports classes.

The notion of "importedDocument" only exists at the LinkImport level
(because its used, HTMLLinkElement has to deal with both importer
and the importee), so we can just call the imported documents simply
"documents" inside of the imports plumbing.

No functional changes, plumbotron.

R=morrita
BUG=

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=175224

[Hajime Morrita, 2014-05-28 20:40:31]

lgtm.

[dglazkov, 2014-06-01 16:44:51]

The CQ bit was checked by dglazkov@chromium.org

[commit-bot: I haz the power, 2014-06-01 16:45:00]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dglazkov@chromium.org/298413004/1

[commit-bot: I haz the power, 2014-06-01 17:57:28]

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

[commit-bot: I haz the power, 2014-06-01 17:57:38]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-06-01 17:57:38]

Try jobs failed on following builders:
  win_gpu_triggered_tests on tryserver.chromium.gpu
(http://build.chromium.org/p/tryserver.chromium.gpu/builders/win_gpu_triggered...)

[dglazkov, 2014-06-01 18:48:20]

The CQ bit was checked by dglazkov@chromium.org

[commit-bot: I haz the power, 2014-06-01 18:48:27]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/dglazkov@chromium.org/298413004/1

[commit-bot: I haz the power, 2014-06-01 18:48:55]

Change committed as 175224