Add keyword_subset field template and generate text-decoration-line.

third_party/WebKit/Source/core/style/ComputedStyle.h

Index: third_party/WebKit/Source/core/style/ComputedStyle.h
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.h b/third_party/WebKit/Source/core/style/ComputedStyle.h
index 13978b9d61d34a662f77d0e7847bcd9f1a858d38..99186c69ceaf060c2e7c582da5ed669512d8b6fe 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.h
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.h
@@ -820,15 +820,6 @@ class ComputedStyle : public ComputedStyleBase,
   }
 
   // Text decoration properties.
-  // text-decoration-line
-  static TextDecoration InitialTextDecoration() {
-    return TextDecoration::kNone;
-  }
-  TextDecoration GetTextDecoration() const {
-    return static_cast<TextDecoration>(TextDecorationInternal());
-  }
-  void SetTextDecoration(TextDecoration v) { SetTextDecorationInternal(v); }
-
   // text-decoration-skip
   static TextDecorationSkip InitialTextDecorationSkip() {
     return TextDecorationSkip::kObjects;