Add plumbing for font-stretch

Source/core/rendering/style/RenderStyle.cpp

Index: Source/core/rendering/style/RenderStyle.cpp
diff --git a/Source/core/rendering/style/RenderStyle.cpp b/Source/core/rendering/style/RenderStyle.cpp
index fbbe571d5af2991f568b5f48244cbd4e9cb4c5cd..d946ccb52e89eaa83a35b43cb18840454d1aa740 100644
--- a/Source/core/rendering/style/RenderStyle.cpp
+++ b/Source/core/rendering/style/RenderStyle.cpp
@@ -1267,6 +1267,15 @@ void RenderStyle::setFontWeight(FontWeight weight)
     font().update(currentFontSelector);
 }
 
+void RenderStyle::setFontStretch(FontStretch stretch)
+{
+    FontSelector* currentFontSelector = font().fontSelector();
+    FontDescription desc(fontDescription());
+    desc.setStretch(stretch);
+    setFontDescription(desc);
+    font().update(currentFontSelector);
+}
+
 void RenderStyle::getShadowExtent(const ShadowList* shadowList, LayoutUnit &top, LayoutUnit &right, LayoutUnit &bottom, LayoutUnit &left) const
 {
     top = 0;