Readd accidentally removed pp:: prefix. Fix build break.
Readd accidentally removed pp:: prefix. Fix build break.

TBR=darin
Review URL: http://codereview.chromium.org/2841036
gwobay/ppapi,cacpssl/ppapi,huqingyu/ppapi,whitewolfm/ppapi,phisixersai/ppapi,dralves/ppapi,whitewolfm/ppapi,fubaydullaev/ppapi,dingdayong/ppapi,chenfeng8742/ppapi,CharlesHuimin/ppapi,huochetou999/ppapi,chenfeng8742/ppapi,thdtjsdn/ppapi,CharlesHuimin/ppapi,ruder/ppapi,c1soju96/ppapi,huochetou999/ppapi,tonyjoule/ppapi,xiaozihui/ppapi,tonyjoule/ppapi,chenfeng8742/ppapi,gwobay/ppapi,YachaoLiu/ppapi,rise-worlds/ppapi,ruder/ppapi,stefanie924/ppapi,phisixersai/ppapi,xuesongzhu/ppapi,huqingyu/ppapi,huochetou999/ppapi,xinghaizhou/ppapi,huochetou999/ppapi,lag945/ppapi,xuesongzhu/ppapi,siweilvxing/ppapi,xinghaizhou/ppapi,gwobay/ppapi,phisixersai/ppapi,dingdayong/ppapi,Xelemsta/ppapi,CharlesHuimin/ppapi,cacpssl/ppapi,fubaydullaev/ppapi,dingdayong/ppapi,nanox/ppapi,chenfeng8742/ppapi,nanox/ppapi,rise-worlds/ppapi,huqingyu/ppapi,whitewolfm/ppapi,YachaoLiu/ppapi,JustRight/ppapi,huqingyu/ppapi,gwobay/ppapi,lag945/ppapi,huochetou999/ppapi,dralves/ppapi,tiaolong/ppapi,tonyjoule/ppapi,phisixersai/ppapi,c1soju96/ppapi,qwop/ppapi,qwop/ppapi,cacpssl/ppapi,tiaolong/ppapi,HAfsari/ppapi,cacpssl/ppapi,ruder/ppapi,rise-worlds/ppapi,siweilvxing/ppapi,tiaolong/ppapi,YachaoLiu/ppapi,JustRight/ppapi,ruder/ppapi,c1soju96/ppapi,tonyjoule/ppapi,xuesongzhu/ppapi,thdtjsdn/ppapi,stefanie924/ppapi,nanox/ppapi,c1soju96/ppapi,JustRight/ppapi,xiaozihui/ppapi,tiaolong/ppapi,stefanie924/ppapi,fubaydullaev/ppapi,stefanie924/ppapi,dingdayong/ppapi,Xelemsta/ppapi,qwop/ppapi,rise-worlds/ppapi,xiaozihui/ppapi,ruder/ppapi,cacpssl/ppapi,HAfsari/ppapi,HAfsari/ppapi,CharlesHuimin/ppapi,thdtjsdn/ppapi,whitewolfm/ppapi,tiaolong/ppapi,JustRight/ppapi,YachaoLiu/ppapi,fubaydullaev/ppapi,thdtjsdn/ppapi,qwop/ppapi,Xelemsta/ppapi,lag945/ppapi,nanox/ppapi,dingdayong/ppapi,HAfsari/ppapi,xinghaizhou/ppapi,xuesongzhu/ppapi,siweilvxing/ppapi,siweilvxing/ppapi,Xelemsta/ppapi,chenfeng8742/ppapi,stefanie924/ppapi,xiaozihui/ppapi,lag945/ppapi,JustRight/ppapi,YachaoLiu/ppapi,phisixersai/ppapi,rise-worlds/ppapi,gwobay/ppapi,CharlesHuimin/ppapi,siweilvxing/ppapi,xuesongzhu/ppapi,dralves/ppapi,xinghaizhou/ppapi,whitewolfm/ppapi,xiaozihui/ppapi,qwop/ppapi,thdtjsdn/ppapi,tonyjoule/ppapi,fubaydullaev/ppapi,huqingyu/ppapi,lag945/ppapi,c1soju96/ppapi,dralves/ppapi,Xelemsta/ppapi,HAfsari/ppapi,xinghaizhou/ppapi,dralves/ppapi,nanox/ppapi