Implements hanging property for text-indent from CSS3

Source/core/rendering/style/RenderStyleConstants.h

Index: Source/core/rendering/style/RenderStyleConstants.h
diff --git a/Source/core/rendering/style/RenderStyleConstants.h b/Source/core/rendering/style/RenderStyleConstants.h
index be263adca6ee840d8fc823d0f41f13ba104d9dd7..0234a169693212460a59dbbc6109c04ff0bff617 100644
--- a/Source/core/rendering/style/RenderStyleConstants.h
+++ b/Source/core/rendering/style/RenderStyleConstants.h
@@ -550,6 +550,7 @@ enum OverflowAlignment {
 static const float maximumAllowedFontSize = 1000000.0f;
 
 enum TextIndentLine { TextIndentFirstLine, TextIndentEachLine };
+enum TextIndentType { TextIndentNormal, TextIndentHanging };
 
 enum CSSBoxType { BoxMissing = 0, MarginBox, BorderBox, PaddingBox, ContentBox };