Fixed issue where style values with an undefined value would get serialized.
Fixed issue where style values with an undefined value would get serialized.

howanghk/tinymce,rbecheras/tinymce,cclaerhout/tinymce,danielpunkass/tinymce,tinymce/tinymce,dziemian007/tinymce,fillabs/TinySpecMCE,enfold/tinymce,widgetfactory/tinymce,kencheung/tinymce,danchr/tinymce,fhchina/tinymce,shilpi230/tinymce,tinymce/tinymce,jtark/tinymce,endjin/tinymce,sjbufton/tinymce,blakewallan/tinymce,danielpunkass/tinymce,kencheung/tinymce,ChristophKaser/tinymce,simachewh/tinymce,ETSI-CTI/TinySpecMCE,Zimbra/tinymce,ChristophKaser/tinymce,leofeyer/tinymce,henrythewasp/tinymce,nbcp/tinymce,fillabs/TinySpecMCE,cclaerhout/tinymce,endjin/tinymce,Razzwan/tinymce,danchr/tinymce,rednose-public/tinymce,gencer/tinymce,bsuh/tinymce,gencer/tinymce,nikolas/tinymce,FernCreek/tinymce,aduth/tinymce,Kindling/tinymce,jtark/tinymce,support-dot-com/tinymce,enfold/tinymce,simachewh/tinymce,Zimbra/tinymce,rednose-public/tinymce,collective/tinymce,nbcp/tinymce,fhchina/tinymce,MediehusetTek/tinymce,M4R7iNP/tinymce,leofeyer/tinymce,rxl194/tinymce,howanghk/tinymce,adaptiffdesigns/tinymce,ikuchmin/tinymce,fashionsun/tinymce,tinymce/tinymce,ice8lue/tinymce,toxalot/tinymce,aduth/tinymce,gabixdev/tinymce,support-dot-com/tinymce,1099511627776/tinymce,rbecheras/tinymce,gabixdev/tinymce,TeamupCom/tinymce,Shopify/tinymce,sachgits/tinymce,dziemian007/tinymce,TeamupCom/tinymce,jashua212/tinymce,pmpl-5/tinymce,mplank/tinymce,M4R7iNP/tinymce,danielpunkass/tinymce,nikolas/tinymce,ice8lue/tinymce,Razzwan/tinymce,1099511627776/tinymce,fashionsun/tinymce,blakewallan/tinymce,collective/tinymce,FernCreek/tinymce,ETSI-CTI/TinySpecMCE,mplank/tinymce,ikuchmin/tinymce,adaptiffdesigns/tinymce,pmpl-5/tinymce,FernCreek/tinymce,Kindling/tinymce,rxl194/tinymce,VioletLife/tinymce,sachgits/tinymce,shilpi230/tinymce,VioletLife/tinymce,MediehusetTek/tinymce,widgetfactory/tinymce,toxalot/tinymce,bsuh/tinymce,jashua212/tinymce,sjbufton/tinymce,henrythewasp/tinymce