Fixes glyphs with invalid flags

src/core/fonts.js

@@ -3163,8 +3163,8 @@ var Font = (function FontClosure() {
         for (var i = 0; i < flagsCount; i++) {
           var flag = glyf[j++];
           if (flag & 0xC0) {
-            // reserved flags must be zero, rejecting
-            return 0;
+            // reserved flags must be zero, cleaning up
+            glyf[j - 1] = flag & 0x3F;
           }
           var xyLength = ((flag & 2) ? 1 : (flag & 16) ? 0 : 2) +
                          ((flag & 4) ? 1 : (flag & 32) ? 0 : 2);

test/pdfs/.gitignore

@@ -46,6 +46,7 @@
 !issue1002.pdf
 !issue925.pdf
 !gradientfill.pdf
+!bug903856.pdf
 !basicapi.pdf
 !mixedfonts.pdf
 !shading_extend.pdf

test/test_manifest.json

@@ -1457,6 +1457,14 @@
        "lastPage": 2,
        "type": "eq"
     },
+    {  "id": "bug903856",
+       "file": "pdfs/bug903856.pdf",
+       "md5": "286eaa9d06a5809f4f08f2093cef8f3f",
+       "rounds": 1,
+       "firstPage": 1,
+       "lastPage": 1,
+       "type": "eq"
+    },
     {  "id": "issue3205",
        "file": "pdfs/issue3205.pdf",
        "md5": "e833326f69f2fdf7c1c8438fe1d3b622",