Bug 1675301 - Don't return web area as result when searching backwards from root group. r=morgan

It seems that VO mistakenly thinks the web area is a descendant of itself. This causes all kinds of cyclical parent child relationships that makes VO over-query us.

This patch remedies that by not returning the web area when do an immediate child search starting from the root group - in any direction.

Differential Revision: https://phabricator.services.mozilla.com/D97819

accessible/mac/MOXSearchInfo.mm

@@ -120,32 +120,24 @@ using namespace mozilla::a11y;
       RotorRule rule =
           mImmediateDescendantsOnly ? RotorRule(geckoRootAcc) : RotorRule();
 
-      if (mSearchForward) {
-        if ([mStartElem isKindOfClass:[MOXWebAreaAccessible class]]) {
-          if (id rootGroup =
-                  [static_cast<MOXWebAreaAccessible*>(mStartElem) rootGroup]) {
-            // Moving forward from web area, rootgroup; if it exists, is next.
-            [matches addObject:rootGroup];
-            if (mResultLimit == 1) {
-              // Found one match, continue in search keys for block.
-              continue;
-            }
+      if ([mStartElem isKindOfClass:[MOXWebAreaAccessible class]]) {
+        if (id rootGroup =
+                [static_cast<MOXWebAreaAccessible*>(mStartElem) rootGroup]) {
+          // Moving forward from web area, rootgroup; if it exists, is next.
+          [matches addObject:rootGroup];
+          if (mResultLimit == 1) {
+            // Found one match, continue in search keys for block.
+            continue;
           }
-        } else if (mImmediateDescendantsOnly && mStartElem != mRoot &&
-                   [mStartElem isKindOfClass:[MOXRootGroup class]]) {
-          // Moving forward from root group. If we don't match descendants,
-          // there is no match. Continue.
-          continue;
-        }
-      } else if (!mSearchForward &&
-                 [mStartElem isKindOfClass:[MOXRootGroup class]]) {
-        // Moving backward from root group. Web area is next.
-        [matches addObject:[mStartElem moxParent]];
-        if (mResultLimit == 1) {
-          // Found one match, continue in search keys for block.
-          continue;
         }
       }
+
+      if (mImmediateDescendantsOnly && mStartElem != mRoot &&
+          [mStartElem isKindOfClass:[MOXRootGroup class]]) {
+        // Moving forward from root group. If we don't match descendants,
+        // there is no match. Continue.
+        continue;
+      }
       [matches addObjectsFromArray:[self getMatchesForRule:rule]];
     }
 

accessible/tests/browser/mac/browser_rotor.js

@@ -1040,11 +1040,10 @@ addAccessibleTask(
       "AXUIElementsForSearchPredicate",
       NSDictionary(searchPred)
     );
-    is(results.length, 1, "WebArea is before root group");
     is(
-      results[0].getAttributeValue("AXRole"),
-      "AXWebArea",
-      "Got web area accessible"
+      results.length,
+      0,
+      "Searching backwards from root group should yield no results"
     );
 
     const rootGroup = webArea.getAttributeValue("AXChildren")[0];