[Experimental] Supporting OOPIF printing

printing/pdf_metafile_skia.h

Index: printing/pdf_metafile_skia.h
diff --git a/printing/pdf_metafile_skia.h b/printing/pdf_metafile_skia.h
index cb69b91685746a42222e3da40aaf5d2344ff455c..5dcec1322a93cce5399d4b56265e62c15c4ef22d 100644
--- a/printing/pdf_metafile_skia.h
+++ b/printing/pdf_metafile_skia.h
@@ -67,6 +67,8 @@ class PRINTING_EXPORT PdfMetafileSkia : public Metafile {
 
   bool SaveTo(base::File* file) const override;
 
+  bool InitFromPageDataBuffer(const char* src_buffer, size_t src_buffer_size);
+
   // Return a new metafile containing just the current page in draft mode.
   std::unique_ptr<PdfMetafileSkia> GetMetafileForCurrentPage(
       SkiaDocumentType type);
@@ -81,6 +83,12 @@ class PRINTING_EXPORT PdfMetafileSkia : public Metafile {
                                       const gfx::Rect& content_area,
                                       const float& scale_factor);
 
+  std::unique_ptr<char[]> GetPageDataBuffer(size_t* size) const;
+
+  void ConvertPagesToPdf();
+  void FinishAllPages();
+  void GetSkp(SkWStream* stream) const;
+
  private:
   std::unique_ptr<PdfMetafileSkiaData> data_;