Replace compile flag with runtime check for text-underline-position

Source/core/css/CSSProperties.in

 // FIXME: When we have all the properties using the new StyleBuilder, we
 //   should use this for make_css_property_names.py
 // Note: Mandatory blank line to skip parameter parsing phase
 
 align-content
 align-items
 align-self type_name=EAlignItems
 background-attachment custom_all
 background-blend-mode custom_all
 background-clip custom_all
@@ skipping 221 matching lines @@
 -webkit-region-fragment type_name=RegionFragment
 -webkit-rtl-ordering type_name=Order, getter=rtlOrdering, setter=setRTLOrdering, initial=initialRTLOrdering
 -webkit-ruby-position type_name=RubyPosition
 -webkit-text-combine type_name=TextCombine
 -webkit-text-emphasis-color custom_all
 -webkit-text-emphasis-position type_name=TextEmphasisPosition
 -webkit-text-emphasis-style custom_all
 -webkit-text-fill-color custom_all
 -webkit-text-security
 -webkit-text-stroke-color custom_all
--webkit-text-underline-position custom_value, condition=CSS3_TEXT
+text-underline-position custom_value
 -webkit-transform-origin-x type_name=Length, converter=convertLength
 -webkit-transform-origin-y type_name=Length, converter=convertLength
 -webkit-transform-origin-z type_name=float, converter=convertComputedLength<float>
 -webkit-transform-style name_for_methods=TransformStyle3D
 -webkit-transition-delay custom_all
 -webkit-transition-duration custom_all
 -webkit-transition-property custom_all
 -webkit-transition-timing-function custom_all
 -webkit-user-drag
 -webkit-user-modify
 -webkit-user-select
 -webkit-wrap-flow type_name=WrapFlow
 -webkit-wrap-through type_name=WrapThrough
 
 alignment-baseline svg
 buffered-rendering svg
 clip-rule svg, type_name=WindRule
 color-interpolation svg
 color-interpolation-filters svg, type_name=EColorInterpolation
 color-rendering svg
 dominant-baseline svg
 fill-rule svg, type_name=WindRule
 mask-type svg
 shape-rendering svg
 stroke-linecap svg, type_name=LineCap, name_for_methods=CapStyle
 stroke-linejoin svg, type_name=LineJoin, name_for_methods=JoinStyle
 text-anchor svg
 vector-effect svg
 writing-mode svg, type_name=SVGWritingMode