SkPDF to use aliased em bounds.

This restores previous behavior and works around a chromium issue.
The underlying issue in DirectWrite will need to be worked around
as well.

Bug: chromium:926885

Change-Id: I6a6cbd04db66066ad258df62d3c9fc8056c33c7f
Reviewed-on: https://skia-review.googlesource.com/c/189167
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Hal Canary <halcanary@google.com>

src/pdf/SkPDFFont.cpp

@@ -34,6 +34,7 @@
 SkExclusiveStrikePtr SkPDFFont::MakeVectorCache(SkTypeface* face, int* size) {
     SkFont font;
     font.setHinting(kNo_SkFontHinting);
+    font.setEdging(SkFont::Edging::kAlias);
     font.setTypeface(sk_ref_sp(face));
     int unitsPerEm = face->getUnitsPerEm();
     if (unitsPerEm <= 0) {