Don't resuse a BrowserAccessibility when our assumption, that is has already been detacted from the tree, doesn't hold.

An investigation as to why our assumption isn't holding needs to take place but this will help prevent BrowserAccessibility tree curruption that leads to crashes in the browser.

BUG=84016
TEST=none
Review URL: http://codereview.chromium.org/7066042

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@87807 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 8 insertions, 6 deletions

diff --git a/chrome/browser/accessibility/browser_accessibility_manager.cc b/chrome/browser/accessibility/browser_accessibility_manager.cc
index c52d0a2..4c58228 100644
--- a/chrome/browser/accessibility/browser_accessibility_manager.cc
+++ b/chrome/browser/accessibility/browser_accessibility_manager.cc
@@ -339,13 +339,15 @@ BrowserAccessibility* BrowserAccessibilityManager::CreateAccessibilityTree(
   if (instance && instance->role() != src.role)
     instance = NULL;
 
-  if (instance) {
-    // If we're reusing a node, it should already be detached from a parent
-    // and any children. If not, that means we have a serious bug somewhere,
-    // like the same child is reachable from two places in the same tree.
-    DCHECK_EQ(static_cast<BrowserAccessibility*>(NULL), instance->parent());
-    DCHECK_EQ(0U, instance->child_count());
+  // If we're reusing a node, it should already be detached from a parent
+  // and any children. If not, that means we have a serious bug somewhere,
+  // like the same child is reachable from two places in the same tree.
+  if (instance && (instance->parent() != NULL || instance->child_count() > 0)) {
+    NOTREACHED();
+    instance = NULL;
+  }
 
+  if (instance) {
     // If we're reusing a node, update its parent and increment its
     // reference count.
     instance->UpdateParent(parent, index_in_parent);