Re-enable solid background color optimization for composited layers.

Source/core/rendering/CompositedLayerMapping.cpp

Index: Source/core/rendering/CompositedLayerMapping.cpp
diff --git a/Source/core/rendering/CompositedLayerMapping.cpp b/Source/core/rendering/CompositedLayerMapping.cpp
index 536a35118a5c0041305fe0dc71df3395a7ec08f9..684d53ac8e7710d860597f818f92fbe352656773 100644
--- a/Source/core/rendering/CompositedLayerMapping.cpp
+++ b/Source/core/rendering/CompositedLayerMapping.cpp
@@ -1268,9 +1268,6 @@ void CompositedLayerMapping::updateBackgroundColor(bool isSimpleContainer)
 
 static bool supportsDirectBoxDecorationsComposition(const RenderObject* renderer)
 {
-    if (!GraphicsLayer::supportsBackgroundColorContent())
-        return false;
-
     if (renderer->hasClip())
         return false;