From 06d1ff5af4b640ddff28c6fe4701f900e70b83ab Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Wed, 8 Aug 2018 12:18:37 +0200
Subject: [PATCH] Tweak the MMType1 font detection in `getFontFileType` to
 improve font telemetry (PR 9961 follow-up)

Please note that this patch does *not* affect rendering in any way, however it's relevant for font telemetry[1].

According to the specification, see https://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/PDF32000_2008.pdf#G8.1904956, Type1C is a valid subtype for *both* Type1 and MMType1 fonts.

---
[1] Refer to the font telemetry results in https://telemetry.mozilla.org/new-pipeline/dist.html#!cumulative=0&end_date=2018-06-25&keys=__none__!__none__!__none__&max_channel_version=nightly%252F62&measure=PDF_VIEWER_FONT_TYPES&min_channel_version=nightly%252F59&processType=*&product=Firefox&sanitize=1&sort_keys=submissions&start_date=2018-05-07&table=0&trim=1&use_submission_date=0

See also https://github.com/mozilla/pdf.js/wiki/Enumeration-Assignments-for-the-Telemetry-Histograms#pdf_viewer_font_types for help with interpreting the data.
---
 src/core/fonts.js | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/core/fonts.js b/src/core/fonts.js
index 5a194a2f62593..8081f1a22a947 100644
--- a/src/core/fonts.js
+++ b/src/core/fonts.js
@@ -717,17 +717,15 @@ var Font = (function FontClosure() {
     } else if (isType1File(file)) {
       if (composite) {
         fileType = 'CIDFontType0';
-      } else if (type === 'MMType1') {
-        fileType = 'MMType1';
       } else {
-        fileType = 'Type1';
+        fileType = (type === 'MMType1' ? 'MMType1' : 'Type1');
       }
     } else if (isCFFFile(file)) {
       if (composite) {
         fileType = 'CIDFontType0';
         fileSubtype = 'CIDFontType0C';
       } else {
-        fileType = 'Type1';
+        fileType = (type === 'MMType1' ? 'MMType1' : 'Type1');
         fileSubtype = 'Type1C';
       }
     } else {