Enable WebVTT regions for runtime testing, updated tests and minor fixes

Source/core/html/track/LoadableTextTrack.cpp

Index: Source/core/html/track/LoadableTextTrack.cpp
diff --git a/Source/core/html/track/LoadableTextTrack.cpp b/Source/core/html/track/LoadableTextTrack.cpp
index 9ccb64b53af3cd7ff940c116f49877a865306d9d..3e182f81fa75a71574f2d2927719b4ba77b50e54 100644
--- a/Source/core/html/track/LoadableTextTrack.cpp
+++ b/Source/core/html/track/LoadableTextTrack.cpp
@@ -24,9 +24,9 @@
  */
 
 #include "config.h"
-
 #include "core/html/track/LoadableTextTrack.h"
 
+#include "RuntimeEnabledFeatures.h"
 #include "core/html/HTMLTrackElement.h"
 #include "core/html/track/TextTrackCueList.h"
 #include "core/html/track/TextTrackRegionList.h"
@@ -128,7 +128,6 @@ void LoadableTextTrack::cueLoadingCompleted(TextTrackLoader* loader, bool loadin
     m_trackElement->didCompleteLoad(this, loadingFailed ? HTMLTrackElement::Failure : HTMLTrackElement::Success);
 }
 
-#if ENABLE(WEBVTT_REGIONS)
 void LoadableTextTrack::newRegionsAvailable(TextTrackLoader* loader)
 {
     ASSERT_UNUSED(loader, m_loader == loader);
@@ -141,7 +140,6 @@ void LoadableTextTrack::newRegionsAvailable(TextTrackLoader* loader)
         regionList()->add(newRegions[i]);
     }
 }
-#endif
 
 size_t LoadableTextTrack::trackElementIndex()
 {