Reapplies all the IPC system work (reverts the revert r56272).

printing/pdf_ps_metafile_cairo.cc

Index: printing/pdf_ps_metafile_cairo.cc
diff --git a/printing/pdf_ps_metafile_cairo.cc b/printing/pdf_ps_metafile_cairo.cc
index 47f4c145e29b4ec6fbd668f21e9b638087446e1e..798ee1608e5898ff9d78452e2bf067b9ddffb26e 100644
--- a/printing/pdf_ps_metafile_cairo.cc
+++ b/printing/pdf_ps_metafile_cairo.cc
@@ -70,6 +70,11 @@ void DestroyContextData(void* data) {
 
 namespace printing {
 
+PdfPsMetafile::PdfPsMetafile()
+    : format_(PDF),
+      surface_(NULL), context_(NULL) {
+}
+
 PdfPsMetafile::PdfPsMetafile(const FileFormat& format)
     : format_(format),
       surface_(NULL), context_(NULL) {