Remove SVG hasExtension() methods

Remove SVG hasExtension() methods

Intent to Deprecate and Remove:
https://groups.google.com/a/chromium.org/d/msg/blink-dev/Ae_lmov16_o/Wa5XhHFoAAAJ

BUG=532405
R=fs@opera.com

Committed: https://crrev.com/22a2b9b39db47a78307c1d1353d0f55e265823ce
Cr-Commit-Position: refs/heads/master@{#350512}

[philipj_slow, 2015-09-23 13:51:10]

The CQ bit was checked by philipj@opera.com to run a CQ dry run

[commit-bot: I haz the power, 2015-09-23 13:51:59]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1359053004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1359053004/1

[commit-bot: I haz the power, 2015-09-23 13:58:21]

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

[commit-bot: I haz the power, 2015-09-23 13:58:22]

Dry run: Try jobs failed on following builders:
  linux_chromium_rel_ng on tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[fs, 2015-09-23 14:13:11]

LGTM (assuming the bots are fine when they stop being exceptional)

[philipj_slow, 2015-09-24 07:46:07]

The CQ bit was checked by philipj@opera.com

[commit-bot: I haz the power, 2015-09-24 07:46:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1359053004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1359053004/1

[commit-bot: I haz the power, 2015-09-24 09:21:04]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2015-09-24 09:21:43]

Patchset 1 (id:??) landed as
https://crrev.com/22a2b9b39db47a78307c1d1353d0f55e265823ce
Cr-Commit-Position: refs/heads/master@{#350512}