[WebVTT] Support text-decoration-{text,color,style} on CSS ::cue pseudo-element

Source/core/css/resolver/StyleResolver.cpp

Index: Source/core/css/resolver/StyleResolver.cpp
diff --git a/Source/core/css/resolver/StyleResolver.cpp b/Source/core/css/resolver/StyleResolver.cpp
index 6f544242c4d57bf8edacbec294f2b9fa4197967a..79ac32954d9df3ace976d343d4a6f5fe1190f5fe 100644
--- a/Source/core/css/resolver/StyleResolver.cpp
+++ b/Source/core/css/resolver/StyleResolver.cpp
@@ -1147,10 +1147,16 @@ static inline bool isValidCueStyleProperty(CSSPropertyID id)
     case CSSPropertyOutlineWidth:
     case CSSPropertyVisibility:
     case CSSPropertyWhiteSpace:
+    // FIXME: 'text-decoration' shorthand to be handled when available.
+    // See https://chromiumcodereview.appspot.com/19516002 for details.
     case CSSPropertyTextDecoration:
     case CSSPropertyTextShadow:
     case CSSPropertyBorderStyle:
         return true;
+    case CSSPropertyTextDecorationLine:
+    case CSSPropertyTextDecorationStyle:
+    case CSSPropertyTextDecorationColor:
+        return RuntimeEnabledFeatures::css3TextDecorationsEnabled();
     default:
         break;
     }