[PDFKit] Update bindings to Xcode 10 Beta 1, 2 & 3#4439

Merged

dalexsoto merged 2 commits intodotnet:xcode10from

dalexsoto:pdfkit10b3

Jul 13, 2018

Commits on Jul 12, 2018

[PDFKit] Update bindings to Xcode 10 Beta 1, 2 & 3
dalexsoto
committed

Commits on Jul 13, 2018

Removes redundant availability attrib and fixes PDFKit library mapping case in xtro
dalexsoto
committed