Bug 1917468 - Remove the unused pdfjs.enableHighlightEditor preferenc…

…e. r=pdfjs-reviewers,robwu

This preference was removed upstream in mozilla/pdf.js#18594, which was uplifted in https://bugzilla.mozilla.org/show_bug.cgi?id=1913880, hence the override should also be removed now.

Differential Revision: https://phabricator.services.mozilla.com/D221411

UltraBlame original commit: c011b9b0def2c394bd90b1837935d502109db725

toolkit/components/nimbus/FeatureManifest.yaml

@@ -1525,12 +1525,6 @@ pdfjs:
   exposureDescription: >-
     Exposure is sent each time a pdf is displayed.
   variables:
-    addHighlight:
-      description: Set to true to highlight some text or something else in an existing pdf.
-      type: boolean
-      setPref:
-        branch: default
-        pref: pdfjs.enableHighlightEditor
     enableAltText:
       description: Set to true to enable alt text generation.
       type: boolean

toolkit/components/pdfjs/PdfJsOverridePrefs.js

@@ -23,8 +23,6 @@
 
 #else
 
-
-  pref("pdfjs.enableHighlightEditor", true);
   #if defined(EARLY_BETA_OR_EARLIER)
     pref("pdfjs.enableHighlightFloatingButton", true);
   #else

toolkit/components/pdfjs/test/browser_pdfjs_editing_contextmenu.js

@@ -359,10 +359,7 @@ add_task(async function test_highlight_selection() {
     { gBrowser, url: "about:blank" },
     async function (browser) {
       await SpecialPowers.pushPrefEnv({
-        set: [
-          ["pdfjs.annotationEditorMode", 0],
-          ["pdfjs.enableHighlightEditor", true],
-        ],
+        set: [["pdfjs.annotationEditorMode", 0]],
       });
 
       await waitAndCheckEmptyContextMenu(browser);