From 4ef187e9032a7bbf319463fd588effb6d2a9d728 Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Fri, 16 Apr 2021 10:08:13 +0200
Subject: [PATCH] Remove the `PDFViewerApplication._delayedFallback`
 functionality

According to a decision by UX and PM, please see https://bugzilla.mozilla.org/show_bug.cgi?id=1705060#c2 (and implemented in https://bugzilla.mozilla.org/show_bug.cgi?id=1705327), we no longer show the notification-bar in Firefox; hence the special `PDFViewerApplication._delayedFallback` functionality should no longer be necessary.
Furthermore, note that at this point in time *most* of the features which used the `PDFViewerApplication._delayedFallback` functionality is now enabled by default; hence that provides even less reason to keep this code around and existing calls are thus converted to "regular" `PDFViewerApplication.fallback` calls.
---
 web/app.js | 52 ++++------------------------------------------------
 1 file changed, 4 insertions(+), 48 deletions(-)

diff --git a/web/app.js b/web/app.js
index 6d74eb6c3..e9a82edd4 100644
--- a/web/app.js
+++ b/web/app.js
@@ -258,7 +258,6 @@ const PDFViewerApplication = {
   metadata: null,
   _contentDispositionFilename: null,
   _contentLength: null,
-  triggerDelayedFallback: null,
   _saveInProgress: false,
   _wheelUnusedTicks: 0,
   _idleCallbacks: new Set(),
@@ -840,7 +839,6 @@ const PDFViewerApplication = {
     this.metadata = null;
     this._contentDispositionFilename = null;
     this._contentLength = null;
-    this.triggerDelayedFallback = null;
     this._saveInProgress = false;
 
     this._cancelIdleCallbacks();
@@ -1021,27 +1019,6 @@ const PDFViewerApplication = {
     }
   },
 
-  /**
-   * For PDF documents that contain e.g. forms and javaScript, we should only
-   * trigger the fallback bar once the user has interacted with the page.
-   * @private
-   */
-  _delayedFallback(featureId) {
-    // Ensure that telemetry is always reported, since it's not guaranteed
-    // that the fallback bar will be shown (depends on user interaction).
-    this.externalServices.reportTelemetry({
-      type: "unsupportedFeature",
-      featureId,
-    });
-
-    if (!this.triggerDelayedFallback) {
-      this.triggerDelayedFallback = () => {
-        this.fallback(featureId);
-        this.triggerDelayedFallback = null;
-      };
-    }
-  },
-
   fallback(featureId) {
     this.externalServices.reportTelemetry({
       type: "unsupportedFeature",
@@ -1513,8 +1490,8 @@ const PDFViewerApplication = {
           // Don't warn/fallback for empty JavaScript actions.
           return false;
         }
-        console.warn("Warning: JavaScript is not supported");
-        this._delayedFallback(UNSUPPORTED_FEATURES.javaScript);
+        console.warn("Warning: JavaScript support is not enabled");
+        this.fallback(UNSUPPORTED_FEATURES.javaScript);
         return true;
       });
 
@@ -1593,13 +1570,13 @@ const PDFViewerApplication = {
       !pdfDocument.isPureXfa
     ) {
       console.warn("Warning: XFA is not supported");
-      this._delayedFallback(UNSUPPORTED_FEATURES.forms);
+      this.fallback(UNSUPPORTED_FEATURES.forms);
     } else if (
       (info.IsAcroFormPresent || info.IsXFAPresent) &&
       !this.pdfViewer.renderInteractiveForms
     ) {
       console.warn("Warning: Interactive form support is not enabled");
-      this._delayedFallback(UNSUPPORTED_FEATURES.forms);
+      this.fallback(UNSUPPORTED_FEATURES.forms);
     }
 
     if (info.IsSignaturesPresent) {
@@ -2006,7 +1983,6 @@ const PDFViewerApplication = {
     });
     window.addEventListener("click", webViewerClick);
     window.addEventListener("keydown", webViewerKeyDown);
-    window.addEventListener("keyup", webViewerKeyUp);
     window.addEventListener("resize", _boundEvents.windowResize);
     window.addEventListener("hashchange", _boundEvents.windowHashChange);
     window.addEventListener("beforeprint", _boundEvents.windowBeforePrint);
@@ -2084,7 +2060,6 @@ const PDFViewerApplication = {
     });
     window.removeEventListener("click", webViewerClick);
     window.removeEventListener("keydown", webViewerKeyDown);
-    window.removeEventListener("keyup", webViewerKeyUp);
     window.removeEventListener("resize", _boundEvents.windowResize);
     window.removeEventListener("hashchange", _boundEvents.windowHashChange);
     window.removeEventListener("beforeprint", _boundEvents.windowBeforePrint);
@@ -2813,15 +2788,6 @@ function webViewerTouchStart(evt) {
 }
 
 function webViewerClick(evt) {
-  // Avoid triggering the fallback bar when the user clicks on the
-  // toolbar or sidebar.
-  if (
-    PDFViewerApplication.triggerDelayedFallback &&
-    PDFViewerApplication.pdfViewer.containsElement(evt.target)
-  ) {
-    PDFViewerApplication.triggerDelayedFallback();
-  }
-
   if (!PDFViewerApplication.secondaryToolbar.isOpen) {
     return;
   }
@@ -2835,16 +2801,6 @@ function webViewerClick(evt) {
   }
 }
 
-function webViewerKeyUp(evt) {
-  if (evt.keyCode === 9) {
-    // The user is tabbing into the viewer. Trigger the fallback bar if it has
-    // not already been displayed.
-    if (PDFViewerApplication.triggerDelayedFallback) {
-      PDFViewerApplication.triggerDelayedFallback();
-    }
-  }
-}
-
 function webViewerKeyDown(evt) {
   if (PDFViewerApplication.overlayManager.active) {
     return;