Remove redundant call to removeAllEventListeners() in Document::open().

From Blink r150175 by <dcheng@chromium.org>
<http://src.chromium.org/viewvc/blink?view=revision&revision=150175>

Document::open() already calls Document::removeAllEventListeners(), which
removes the event listeners from the DOMWindow it's attached to, so
there's no need to do it manually here as well.

* dom/Document.cpp:
(WebCore::Document::open):

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149957 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Devirtualize some things on Document.

From Blink r149967 by <esprehn@chromium.org>
<http://src.chromium.org/viewvc/blink?view=revision&revision=149967>

Several methods on Document are virtual but don't override a super class method
and don't need to be virtual. This patch devirtualizes:

    - createElementNS()
    - finishedParsing()
    - suspendScriptedAnimationControllerCallbacks()
    - resumeScriptedAnimationControllerCallbacks()

It also removes the suspend and resume callbacks from ScriptExecutionContext
since they didn't need to be there.

* dom/Document.h:
* dom/ScriptExecutionContext.h:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@149959 268f45cc-cd09-0410-ab3c-d52691b4dbfc