Demote 'line-height' to a low priority property.

Source/core/css/resolver/StyleResolverState.h

Index: Source/core/css/resolver/StyleResolverState.h
diff --git a/Source/core/css/resolver/StyleResolverState.h b/Source/core/css/resolver/StyleResolverState.h
index 10b02d855fcb197cb62e8f8ed6a98e1fa566cd5a..5665c86c15c2331ba4f5a0ef10dc2e241c9e2465 100644
--- a/Source/core/css/resolver/StyleResolverState.h
+++ b/Source/core/css/resolver/StyleResolverState.h
@@ -93,9 +93,6 @@ public:
     // Holds all attribute names found while applying "content" properties that contain an "attr()" value.
     Vector<AtomicString>& contentAttrValues() { return m_contentAttrValues; }
 
-    void setLineHeightValue(CSSValue* value) { m_lineHeightValue = value; }
-    CSSValue* lineHeightValue() { return m_lineHeightValue; }
-
     void cacheUserAgentBorderAndBackground()
     {
         // RenderTheme only needs the cached style if it has an appearance,
@@ -153,8 +150,6 @@ private:
     bool m_applyPropertyToRegularStyle;
     bool m_applyPropertyToVisitedLinkStyle;
 
-    RawPtrWillBeMember<CSSValue> m_lineHeightValue;
-
     FontBuilder m_fontBuilder;
 
     OwnPtr<CachedUAStyle> m_cachedUAStyle;