Fix loading accessibility tree for child frame that's already loaded.

content/browser/accessibility/dump_accessibility_browsertest_base.h

Index: content/browser/accessibility/dump_accessibility_browsertest_base.h
diff --git a/content/browser/accessibility/dump_accessibility_browsertest_base.h b/content/browser/accessibility/dump_accessibility_browsertest_base.h
index 58a69bcfade7c7613d29cf5a4a28e5ebd3f37c1c..32762eea89e5c92c79028a49fa58ab4f1b0640ca 100644
--- a/content/browser/accessibility/dump_accessibility_browsertest_base.h
+++ b/content/browser/accessibility/dump_accessibility_browsertest_base.h
@@ -107,6 +107,10 @@ class DumpAccessibilityTestBase : public ContentBrowserTest {
 
   // Whether we're doing a native pass or internal/blink tree pass.
   bool is_blink_pass_;
+
+  // Whether we should enable accessibility after navigating to the page,
+  // otherwise we enable it first.
+  bool enable_accessibility_after_navigating_;
 };
 
 }  // namespace content