Remove the Element.prefix setter

Remove the Element.prefix setter

Intent to Remove:
https://groups.google.com/a/chromium.org/d/msg/blink-dev/bka_hQuzAu0/tjD-GhJ6zDAJ

Attribute::setPrefix() was unused and showed up in grep.

BUG=431552
Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=185009

[philipj_slow, 2014-10-31 12:39:52]

remove tests

[philipj_slow, 2014-11-04 22:26:21]

philipj@opera.com changed reviewers:
+ pdr@chromium.org

[philipj_slow, 2014-11-04 22:26:21]

PTAL

[pdr., 2014-11-07 02:23:42]

The CQ bit was checked by pdr@chromium.org

[pdr., 2014-11-07 02:23:42]

LGTM. Sorry for the delay (blinkon)

[commit-bot: I haz the power, 2014-11-07 02:24:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/688333002/20001

[commit-bot: I haz the power, 2014-11-07 02:24:50]

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

[commit-bot: I haz the power, 2014-11-07 02:24:51]

Failed to apply patch for
LayoutTests/fast/dom/element-attribute-js-null-expected.txt:
While running patch -p1 --forward --force --no-backup-if-mismatch;
  patching file LayoutTests/fast/dom/element-attribute-js-null-expected.txt
  Hunk #1 FAILED at 1.
  1 out of 1 hunk FAILED -- saving rejects to file
LayoutTests/fast/dom/element-attribute-js-null-expected.txt.rej

Patch:       LayoutTests/fast/dom/element-attribute-js-null-expected.txt
Index: LayoutTests/fast/dom/element-attribute-js-null-expected.txt
diff --git a/LayoutTests/fast/dom/element-attribute-js-null-expected.txt
b/LayoutTests/fast/dom/element-attribute-js-null-expected.txt
index
8c4434141aaf6289db6d31d490ee2748bbd294db..79985874f65aa1db41f5b47d6fd9b0867c5eb9ac
100644
--- a/LayoutTests/fast/dom/element-attribute-js-null-expected.txt
+++ b/LayoutTests/fast/dom/element-attribute-js-null-expected.txt
@@ -1,9 +1,7 @@
-CONSOLE WARNING: Setting 'Element.prefix' is deprecated, as it is read-only per
DOM (http://dom.spec.whatwg.org/#element).
 CONSOLE WARNING: 'HTMLHeadElement.profile' is deprecated. The reflected
attribute has no effect.
 This test setting various attributes of a elements to JavaScript null.
 
 TEST SUCCEEDED: The value was null. [tested Node.nodeValue]
-TEST SUCCEEDED: The value was null. [tested Node.prefix]
 TEST SUCCEEDED: The value was the empty string. [tested Node.textContent]
 
 TEST SUCCEEDED: The value was the string 'null'. [tested Element.id]

[philipj_slow, 2014-11-08 21:29:37]

rebase

[philipj_slow, 2014-11-08 21:43:08]

The CQ bit was checked by philipj@opera.com

[commit-bot: I haz the power, 2014-11-08 21:43:46]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/688333002/40001

[commit-bot: I haz the power, 2014-11-08 22:48:39]

Committed patchset #3 (id:40001) as 185009