fix(autocomplete): fix a11y violations (#5241)

Accessibility violations for autocompletion popover are fixed.

    role=listbox is moved to $textLayer of ace_autocomplete editor to make its direct children have role=option, otherwise there is aria-required-children violation (https://dequeuniversity.com/rules/axe/4.5/aria-required-children?application=axeAPI)
    aria-hidden set for textarea of autocomplete popover (there is textarea there since it is an editor instance).
    aria-posinset now starts from 1.

src/autocomplete/popup.js

@@ -50,8 +50,9 @@ class AcePopup {
         popup.renderer.setStyle("ace_autocomplete");
 
         // Set aria attributes for the popup
-        popup.renderer.container.setAttribute("role", "listbox");
-        popup.renderer.container.setAttribute("aria-label", nls("Autocomplete suggestions"));
+        popup.renderer.$textLayer.element.setAttribute("role", "listbox");
+        popup.renderer.$textLayer.element.setAttribute("aria-label", nls("Autocomplete suggestions"));
+        popup.renderer.textarea.setAttribute("aria-hidden", "true");
 
         popup.setOption("displayIndentGuides", false);
         popup.setOption("dragDelay", 150);
@@ -133,12 +134,12 @@ class AcePopup {
                 dom.addCssClass(selected, "ace_selected");
                 var ariaId = getAriaId(row);
                 selected.id = ariaId;
-                popup.renderer.container.setAttribute("aria-activedescendant", ariaId);
+                t.element.setAttribute("aria-activedescendant", ariaId);
                 el.setAttribute("aria-activedescendant", ariaId);
                 selected.setAttribute("role", "option");
                 selected.setAttribute("aria-label", popup.getData(row).value);
                 selected.setAttribute("aria-setsize", popup.data.length);
-                selected.setAttribute("aria-posinset", row);
+                selected.setAttribute("aria-posinset", row+1);
                 selected.setAttribute("aria-describedby", "doc-tooltip");
             }
         });

src/autocomplete_test.js

@@ -48,16 +48,16 @@ module.exports = {
         assert.ok(!editor.container.querySelector("style"));
 
         sendKey("a");
-        checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="arraysort" aria-setsize="2" aria-posinset="0" aria-describedby="doc-tooltip"><s "ace_completion-highlight">a</s><s "ace_">rraysort</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d><d "ace_line"><s "ace_completion-highlight">a</s><s "ace_">looooooooooooooooooooooooooooong_word</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
+        checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="arraysort" aria-setsize="2" aria-posinset="1" aria-describedby="doc-tooltip"><s "ace_completion-highlight">a</s><s "ace_">rraysort</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d><d "ace_line"><s "ace_completion-highlight">a</s><s "ace_">looooooooooooooooooooooooooooong_word</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
             sendKey("rr");
-            checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="arraysort" aria-setsize="1" aria-posinset="0" aria-describedby="doc-tooltip"><s "ace_completion-highlight">arr</s><s "ace_">aysort</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
+            checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="arraysort" aria-setsize="1" aria-posinset="1" aria-describedby="doc-tooltip"><s "ace_completion-highlight">arr</s><s "ace_">aysort</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
                 sendKey("r");
-                checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="arraysort" aria-setsize="1" aria-posinset="0" aria-describedby="doc-tooltip"><s "ace_completion-highlight">arr</s><s "ace_">ayso</s><s "ace_completion-highlight">r</s><s "ace_">t</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
+                checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="arraysort" aria-setsize="1" aria-posinset="1" aria-describedby="doc-tooltip"><s "ace_completion-highlight">arr</s><s "ace_">ayso</s><s "ace_completion-highlight">r</s><s "ace_">t</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
 
                     sendKey("Return");
                     assert.equal(editor.getValue(), "arraysort\narraysort alooooooooooooooooooooooooooooong_word");
                     editor.execCommand("insertstring", " looooooooooooooooooooooooooooong_");
-                    checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="alooooooooooooooooooooooooooooong_word" aria-setsize="1" aria-posinset="0" aria-describedby="doc-tooltip"><s "ace_">a</s><s "ace_completion-highlight">looooooooooooooooooooooooooooong_</s><s "ace_">word</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
+                    checkInnerHTML('<d "ace_line ace_selected" id="suggest-aria-id:0" role="option" aria-label="alooooooooooooooooooooooooooooong_word" aria-setsize="1" aria-posinset="1" aria-describedby="doc-tooltip"><s "ace_">a</s><s "ace_completion-highlight">looooooooooooooooooooooooooooong_</s><s "ace_">word</s><s "ace_completion-spacer"> </s><s "ace_completion-meta">local</s></d>', function() {
                         sendKey("Return");
                         editor.destroy();
                         editor.container.remove();