Expand system font values during font property parsing

Source/web/tests/DragImageTest.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 133 matching lines @@
     }
 }
 
 TEST(DragImageTest, TrimWhitspace)
 {
     KURL url = toKURL("http://www.example.com/");
     String testLabel = "          Example Example Example      \n    ";
     String expectedLabel = "Example Example Example";
     float deviceScaleFactor = 1.0f;
     FontDescription fontDescription;
-    RenderTheme::theme().systemFont(WebCore::CSSValueNone, fontDescription);
+    RenderTheme::theme().systemFont(WebCore::CSSValueCaption, fontDescription);
 
     OwnPtr<DragImage> testImage =
         DragImage::create(url, testLabel, fontDescription, deviceScaleFactor);
     OwnPtr<DragImage> expectedImage =
         DragImage::create(url, expectedLabel, fontDescription, deviceScaleFactor);
 
     EXPECT_EQ(testImage->size().width(), expectedImage->size().width());
 }
 
 } // anonymous namespace