[orca] Revert "Mouse Review: Do full tree dive to locate all document candidates at point"

[Joanmarie Diggs <joanied src gnome org>]

commit 4446b3ad258c185b9fee8b9655019e50b355ed40
Author: Joanmarie Diggs <jdiggs igalia com>
Date:   Thu Nov 21 08:40:59 2019 -0500

    Revert "Mouse Review: Do full tree dive to locate all document candidates at point"
    
    This reverts commit 31c118d7d6f2e3b1f3d11de0fc192a7e71d0188a.

 src/orca/scripts/web/script_utilities.py | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)
---
diff --git a/src/orca/scripts/web/script_utilities.py b/src/orca/scripts/web/script_utilities.py
index 79d1cb651..bce0d639e 100644
--- a/src/orca/scripts/web/script_utilities.py
+++ b/src/orca/scripts/web/script_utilities.py
@@ -4581,15 +4581,22 @@ class Utilities(script_utilities.Utilities):
         if coordType is None:
             coordType = pyatspi.DESKTOP_COORDS
 
-        if not self.inDocumentContent(root):
+        if not (root and self.inDocumentContent(root)):
             return super().descendantAtPoint(root, x, y, coordType)
 
-        isMatch = lambda o: self.containsPoint(o, x, y, coordType)
-        candidates = self.findAllDescendants(root, isMatch)
+        if self.containsPoint(root, x, y, coordType):
+            return super().descendantAtPoint(root, x, y, coordType)
 
-        isPresentable = lambda x: x and (x.name or self.hasPresentableText(x))
-        candidates = list(filter(isPresentable, candidates))
-        if len(candidates) == 1:
-            return candidates[0]
+        # Authoring can cause user agents to expose containers with a bounding
+        # box that doesn't contain the child container at the specified point.
+        obj = root
+        for child in root:
+            if self.containsPoint(child, x, y, coordType):
+                obj = child
+                break
+        else:
+            child = root.queryComponent().getAccessibleAtPoint(x, y, coordType)
+            if child and self.containsPoint(child, x, y, coordType):
+                return child
 
-        return super().descendantAtPoint(root, x, y, coordType)
+        return super().descendantAtPoint(obj, x, y, coordType)