https://bugs.webkit.org/show_bug.cgi?id=108882

Reviewed by Eric Carlson.

Source/WebCore:

On Mac, we want a specific format for menu items in a caption list. Since
other ports might want different formats, move the generation of the label
into CaptionsUserPreferences where it can be overridden.

This required CaptionsUserPreferences to become public on the PageGroup, so
it could be used when creating the menu. Also, since CaptionsUserPreferences
was hidden on Mountain Lion and below, be a little more specific about
which pieces can be seen on which builds.

Covered by existing media/video-controls-captions-trackmenu tests.

* English.lproj/Localizable.strings: Remove textTrackClosedCaptionsText.
* html/shadow/MediaControlElements.cpp:
(WebCore::MediaControlClosedCaptionsTrackListElement::rebuildTrackListMenu): Build only
    one section and get the track's display name from the user preferences.
* page/CaptionUserPreferences.h:
(WebCore::CaptionUserPreferences::displayNameForTrack): Default implementation of
    virtual function that provides a label for a captions menu item.
* page/CaptionUserPreferencesMac.h: Add the new virtual function, and expose just
    a bit of this class outside 10.9 builds.
* page/CaptionUserPreferencesMac.mm:
(WebCore::CaptionUserPreferencesMac::CaptionUserPreferencesMac): Guard features for system version.
(WebCore::CaptionUserPreferencesMac::~CaptionUserPreferencesMac): Ditto.
(WebCore::CaptionUserPreferencesMac::displayNameForTrack): New OS X-specific method that
    returns a string for the menu label.
* page/PageGroup.cpp:
(WebCore::PageGroup::captionPreferences): Unguard for system version.
* page/PageGroup.h: Make captionPreferences public.
* platform/LocalizedStrings.cpp: Remove textTrackClosedCaptionsText - not needed any more.
* platform/LocalizedStrings.h: Remove textTrackClosedCaptionsText.

LayoutTests:

Now that the captions menu can be labelled in a platform-specific way, move
the results into the platform directory. At the moment, they are skipped
everywhere but Mac. Also update the tests to the new menu structure, which
only has a single list of entries.

* media/video-controls-captions-trackmenu-localized.html: Updated for new menu structure.
* media/video-controls-captions-trackmenu-expected.txt: Removed.
* media/video-controls-captions-trackmenu-localized-expected.txt: Removed.
* media/video-controls-captions-trackmenu-sorted-expected.txt: Removed.
* media/video-controls-captions-trackmenu-sorted.html: Updated for new menu structure.
* media/video-controls-captions-trackmenu.html: Updated for new menu structure.
* platform/mac/media/video-controls-captions-trackmenu-expected.txt: New platform specific results.
* platform/mac/media/video-controls-captions-trackmenu-localized-expected.txt: Ditto.
* platform/mac/media/video-controls-captions-trackmenu-sorted-expected.txt: Ditto.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@141864 268f45cc-cd09-0410-ab3c-d52691b4dbfc