[Mac] .webkitClosedCaptionsVisible doesn't work with "Automatic" caption mode
https://bugs.webkit.org/show_bug.cgi?id=118319

Reviewed by Jer Noble.

Source/WebCore: 

Track when captions are enabled with the old 'webkitClosedCaptionsVisible' attribute and
consider that when determining which track should be enabled.

Test: media/track/track-legacyapi-with-automatic-mode.html

* html/HTMLMediaElement.cpp:
(WebCore::HTMLMediaElement::HTMLMediaElement): Initialize m_webkitLegacyClosedCaptionOverride.
(WebCore::HTMLMediaElement::setWebkitClosedCaptionsVisible): Set m_webkitLegacyClosedCaptionOverride.
(WebCore::HTMLMediaElement::webkitClosedCaptionsVisible): Return m_webkitLegacyClosedCaptionOverride.
* html/HTMLMediaElement.h:

* page/CaptionUserPreferencesMediaAF.cpp:
(WebCore::CaptionUserPreferencesMediaAF::textTrackSelectionScore): Don't apply "automatic"
    logic when captions were enabled with .webkitClosedCaptionsVisible.

LayoutTests: 

* media/track/track-legacyapi-with-automatic-mode-expected.txt: Added.
* media/track/track-legacyapi-with-automatic-mode.html: Added.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@152422 268f45cc-cd09-0410-ab3c-d52691b4dbfc
Unreviewed. Add myself as a committer.

* Scripts/webkitpy/common/config/contributors.json:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@152423 268f45cc-cd09-0410-ab3c-d52691b4dbfc