[Linux] Enable subpixel text on high-dpi regardless of hinting

Source/core/rendering/RenderLayer.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 1791 matching lines @@
     // If it were painted in the foreground phase, it would move with the scrolled
     // content. When not composited scrolling, the outline is painted in the
     // foreground phase. Since scrolled contents are moved by repainting in this
     // case, the outline won't get 'dragged along'.
     bool shouldPaintOutline = isSelfPaintingLayer && !isPaintingOverlayScrollbars
         && ((isPaintingScrollingContent && isPaintingCompositedBackground)
         || (!isPaintingScrollingContent && isPaintingCompositedForeground));
     bool shouldPaintContent = m_hasVisibleContent && isSelfPaintingLayer && !isPaintingOverlayScrollbars;
 
     float deviceScaleFactor = WebCore::deviceScaleFactor(renderer()->frame());
-    context->setUseHighResMarkers(deviceScaleFactor > 1.5f);
+    context->setDeviceScaleFactor(deviceScaleFactor);
 
     GraphicsContext* transparencyLayerContext = context;
 
     if (paintFlags & PaintLayerPaintingRootBackgroundOnly && !renderer()->isRenderView() && !renderer()->isDocumentElement())
         return;
 
     // Ensure our lists are up-to-date.
     m_stackingNode->updateLayerListsIfNeeded();
 
     LayoutPoint offsetFromRoot;
@@ skipping 1963 matching lines @@
     }
 }
 
 void showLayerTree(const WebCore::RenderObject* renderer)
 {
     if (!renderer)
         return;
     showLayerTree(renderer->enclosingLayer());
 }
 #endif