Skia minor version tracks milestone release branch

src/pdf/SkPDFMetadata.cpp

Index: src/pdf/SkPDFMetadata.cpp
diff --git a/src/pdf/SkPDFMetadata.cpp b/src/pdf/SkPDFMetadata.cpp
index 5e8c124d7b6cb5d3351d4f095710ffd83fc061c0..b70446d43e6925070ecd0389efa890f5283cb469 100644
--- a/src/pdf/SkPDFMetadata.cpp
+++ b/src/pdf/SkPDFMetadata.cpp
@@ -26,6 +26,8 @@ static SkString pdf_date(const SkTime::DateTime& dt) {
             static_cast<unsigned>(dt.fSecond), timezoneSign, timeZoneHours,
             timeZoneMinutes);
 }
+#define SKPDF_STRING(X) SKPDF_STRING_IMPL(X)
+#define SKPDF_STRING_IMPL(X) #X
 
 SkPDFObject* SkPDFMetadata::createDocumentInformationDict() const {
     auto dict = sk_make_sp<SkPDFDict>();
@@ -38,7 +40,7 @@ SkPDFObject* SkPDFMetadata::createDocumentInformationDict() const {
             }
         }
     }
-    dict->insertString("Producer", "Skia/PDF");
+    dict->insertString("Producer", "Skia/PDF m" SKPDF_STRING(SKIA_MILESTONE));
     if (fCreation) {
         dict->insertString("CreationDate", pdf_date(*fCreation.get()));
     }