bug fix when use NSShadow without YYTextShadow: #122

YYText/Component/YYTextLayout.m

@@ -772,7 +772,7 @@ OSSpinLockUnlock(&_lock);
             if (attrs[YYTextHighlightAttributeName]) layout.containsHighlight = YES;
             if (attrs[YYTextBlockBorderAttributeName]) layout.needDrawBlockBorder = YES;
             if (attrs[YYTextBackgroundBorderAttributeName]) layout.needDrawBackgroundBorder = YES;
-            if (attrs[YYTextShadowAttributeName]) layout.needDrawShadow = YES;
+            if (attrs[YYTextShadowAttributeName] || attrs[NSShadowAttributeName]) layout.needDrawShadow = YES;
             if (attrs[YYTextUnderlineAttributeName]) layout.needDrawUnderline = YES;
             if (attrs[YYTextAttachmentAttributeName]) layout.needDrawAttachment = YES;
             if (attrs[YYTextInnerShadowAttributeName]) layout.needDrawInnerShadow = YES;