ChromeVox: Correctly recover focus when collapsing the Panel.

This change fixes a regression that was introduced by adding in-page
link support for ChromeVox. The issue is that when the panel is
collapsed, a scrolled_to_anchor event is fired, which was causing us
to always place focus on the Panel root web area upon collapsing the
menus. To fix the issue, we ignore scrolled_to_anchor events if the
root of the target differs from the root of the current range.

Fixed: 1133548
AX-Relnotes: N/A
Change-Id: I43e99452ea27cd190bd53c62b5fb06593a5bf6b9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2442899
Commit-Queue: Akihiro Ota <akihiroota@chromium.org>
Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#813000}

chrome/browser/resources/chromeos/accessibility/chromevox/background/desktop_automation_handler.js

@@ -83,7 +83,7 @@ DesktopAutomationHandler = class extends BaseAutomationHandler {
         EventType.SCROLL_VERTICAL_POSITION_CHANGED,
         this.onScrollPositionChanged);
     // Called when a same-page link is followed or the url fragment changes.
-    this.addListener_(EventType.SCROLLED_TO_ANCHOR, this.onEventDefault);
+    this.addListener_(EventType.SCROLLED_TO_ANCHOR, this.onScrolledToAnchor);
     this.addListener_(EventType.SELECTION, this.onSelection);
     this.addListener_(EventType.TEXT_CHANGED, this.onEditableChanged_);
     this.addListener_(
@@ -548,6 +548,29 @@ DesktopAutomationHandler = class extends BaseAutomationHandler {
     }.bind(this));
   }
 
+  /**
+   * Provides all feedback once a scrolled to anchor event fires.
+   * @param {!ChromeVoxEvent} evt
+   */
+  onScrolledToAnchor(evt) {
+    if (!evt.target) {
+      return;
+    }
+
+    if (ChromeVoxState.instance.currentRange) {
+      const target = evt.target;
+      const current = ChromeVoxState.instance.currentRange.start.node;
+      if (AutomationUtil.getTopLevelRoot(current) !=
+          AutomationUtil.getTopLevelRoot(target)) {
+        // Ignore this event if the root of the target differs from that of the
+        // current range.
+        return;
+      }
+    }
+
+    this.onEventDefault(evt);
+  }
+
   /**
    * Create an editable text handler for the given node if needed.
    * @param {!AutomationNode} node

chrome/browser/resources/chromeos/accessibility/chromevox/panel/panel.js

@@ -1112,7 +1112,7 @@ Panel = class {
       desktop.addEventListener(
           chrome.automation.EventType.FOCUS, onFocus, true);
 
-      // Make sure all menus are cleared to avoid bogous output when we re-open.
+      // Make sure all menus are cleared to avoid bogus output when we re-open.
       Panel.clearMenus();
 
       // Ensure annotations input is cleared.