Forward four more BrowserAccessibility APIs to AXPlatformNode.

ui/views/accessibility/native_view_accessibility_auralinux.cc

Index: ui/views/accessibility/native_view_accessibility_auralinux.cc
diff --git a/ui/views/accessibility/native_view_accessibility_auralinux.cc b/ui/views/accessibility/native_view_accessibility_auralinux.cc
index 89b42737d057a96e50c82f66d08430ea8f50521c..a5a06d4da8d50f6cba8884ea7694e4fad0132f4c 100644
--- a/ui/views/accessibility/native_view_accessibility_auralinux.cc
+++ b/ui/views/accessibility/native_view_accessibility_auralinux.cc
@@ -72,6 +72,11 @@ class AuraLinuxApplication
 
   const ui::AXNodeData& GetData() const override { return data_; }
 
+  const ui::AXTreeData& GetTreeData() const override {
+    CR_DEFINE_STATIC_LOCAL(ui::AXTreeData, empty_data, ());
+    return empty_data;
+  }
+
   gfx::NativeWindow GetTopLevelWidget() override { return nullptr; }
 
   gfx::NativeViewAccessible GetParent() override {