https://bugs.webkit.org/show_bug.cgi?id=110725

Reviewed by Eric Carlson.

When settings are changed, do not re-query the media engines (which causes their respective
frameworks to load). Instead, merely clear any previously loaded media engines so that
the media engine list will be re-queried the next time installedMediaEngines() is called.

(WebCore::MediaPlayer::resetMediaEngines): Renamed from requeryMediaEngines.
* platform/graphics/MediaPlayer.h:
* html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::resetMediaEngines): Ditto.
* html/HTMLMediaElement.h:
* page/Settings.cpp:
(WebCore::Settings::setAVFoundationEnabled): Call renamed method.
(WebCore::Settings::setQTKitEnabled):  Ditto.
* platform/graphics/MediaPlayer.cpp:
(WebCore::installedMediaEngines): Only clear out previously queried engines.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@143945 268f45cc-cd09-0410-ab3c-d52691b4dbfc