Reland "Add plumbing for font-stretch"

Source/core/rendering/style/RenderStyle.h

Index: Source/core/rendering/style/RenderStyle.h
diff --git a/Source/core/rendering/style/RenderStyle.h b/Source/core/rendering/style/RenderStyle.h
index 9bb1aae8b6a2bd6877862a2530c90609b76aee90..03a59cea844f8cb0f10c9c9d92a570543d5d5581 100644
--- a/Source/core/rendering/style/RenderStyle.h
+++ b/Source/core/rendering/style/RenderStyle.h
@@ -557,6 +557,7 @@ public:
     float computedFontSize() const;
     int fontSize() const;
     FontWeight fontWeight() const;
+    FontStretch fontStretch() const;
 
     float textAutosizingMultiplier() const { return inherited->textAutosizingMultiplier; }
 
@@ -1107,6 +1108,7 @@ public:
     bool setFontDescription(const FontDescription&);
     // Only used for blending font sizes when animating and for text autosizing.
     void setFontSize(float);
+    void setFontStretch(FontStretch);
     void setFontWeight(FontWeight);
 
     void setTextAutosizingMultiplier(float v)