Replace a stale fixme with a comment

Source/core/css/parser/SizesAttributeParser.cpp

Index: Source/core/css/parser/SizesAttributeParser.cpp
diff --git a/Source/core/css/parser/SizesAttributeParser.cpp b/Source/core/css/parser/SizesAttributeParser.cpp
index d46afb0c345ac92e26fbee4f39931f967dd3349e..ce64693c241d448d72be1f288ee3d4bc33429e11 100644
--- a/Source/core/css/parser/SizesAttributeParser.cpp
+++ b/Source/core/css/parser/SizesAttributeParser.cpp
@@ -73,7 +73,7 @@ static void reverseSkipUntilComponentStart(MediaQueryTokenIterator& token, Media
 
 bool SizesAttributeParser::mediaConditionMatches(PassRefPtrWillBeRawPtr<MediaQuerySet> mediaCondition)
 {
-    // FIXME: How do I handle non-screen media types here?
+    // A Media Condition cannot have a media type other then screen.

[ojan, 2014/05/16 18:21:56]

Can you make this an ASSERT instead of a comment?

[cbiesinger, 2014/05/16 18:25:44]

The comment is just explaining why the next line always passes in "screen"

     MediaQueryEvaluator mediaQueryEvaluator(MediaTypeNames::screen, *m_mediaValues);
     return mediaQueryEvaluator.eval(mediaCondition.get());
 }