Fix text spacing with vertical fonts. #7687 and #11526.

When the writing mode is vertical, we have to reverse
the sign of spacing since we are subtracting it from
current.y. We have to add it to current.y.
See 9.4.4 Text Space Details, https://www.adobe.com/content/dam/acom/en/devnet/acrobat/pdfs/PDF32000_2008.pdf#G8.1694762

src/display/canvas.js

@@ -1719,7 +1719,12 @@ var CanvasGraphics = (function CanvasGraphicsClosure() {
           }
         }
 
-        var charWidth = width * widthAdvanceScale + spacing * fontDirection;
+        var charWidth;
+        if (vertical) {
+          charWidth = width * widthAdvanceScale - spacing * fontDirection;
+        } else {
+          charWidth = width * widthAdvanceScale + spacing * fontDirection;
+        }
         x += charWidth;
 
         if (restoreNeeded) {

test/pdfs/issue11526.pdf.link

@@ -0,0 +1 @@
+https://web.archive.org/web/20200210200830/https://www.nta.go.jp/taxes/tetsuzuki/shinsei/shinkoku/zoyo/yoshiki2019/pdf/006.pdf

test/test_manifest.json

@@ -4376,5 +4376,13 @@
       "rounds": 1,
       "link": false,
       "type": "eq"
+    },
+    { "id": "issue11526",
+      "file": "pdfs/issue11526.pdf",
+      "md5": "9babc771fc8792f43e4ada46b0daff8c",
+      "rounds": 1,
+      "lastPage": 1,
+      "link": true,
+      "type": "eq"
     }
 ]