Update precompiled pdfium for mac to chromium/3071 and add version info file with minimal build instructions

common/pdf_comic.h

@@ -0,0 +1,44 @@
+#if !defined PDF_COMIC_H && !defined NO_PDF
+#define PDF_COMIC_H
+
+#include <QObject>
+#include <QImage>
+
+#if defined Q_OS_MAC && defined USE_PDFKIT
+class MacOSXPDFComic
+{
+	public:
+		MacOSXPDFComic();
+		~MacOSXPDFComic();
+		bool openComic(const QString & path);
+		void closeComic();
+		unsigned int numPages();
+		QImage getPage(const int page);
+        //void releaseLastPageData();
+	
+	private:
+		void * document;
+		void * lastPageData;
+	};
+
+#elif defined USE_PDFIUM
+#include <fpdfview.h>
+
+class PdfiumComic
+{
+	public:
+		PdfiumComic();
+		~PdfiumComic();
+		bool openComic(const QString & path);
+		void closeComic();
+		unsigned int numPages();
+		QImage getPage(const int page);
+	
+	private:
+		FPDF_LIBRARY_CONFIG config;
+		FPDF_DOCUMENT doc;
+};
+#else
+#include "poppler-qt5.h"
+#endif // Q_OS_MAC
+#endif // PDF_COMIC_H