wasm: fix accessibility crash on null parent

The code was a assuming that an a11y interface always
has a parent, which is not the case for the root interface.
Also factor out to a getWindow() function, to prepare
for re-use later on.

Change-Id: I52a841bf94c712deb9603e8b9c2c878820c5f117
Reviewed-by: Mikołaj Boc <Mikolaj.Boc@qt.io>
(cherry picked from commit 34c36821578f39e9c7f99e1dd0e7887a52418b9d)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

2 files changed, 12 insertions, 10 deletions

diff --git a/src/plugins/platforms/wasm/qwasmaccessibility.cpp b/src/plugins/platforms/wasm/qwasmaccessibility.cpp
index e9217cbefc..bea7380bfc 100644
--- a/src/plugins/platforms/wasm/qwasmaccessibility.cpp
+++ b/src/plugins/platforms/wasm/qwasmaccessibility.cpp
@@ -113,17 +113,18 @@ emscripten::val QWasmAccessibility::getContainer(QWindow *window)
 
 emscripten::val QWasmAccessibility::getContainer(QAccessibleInterface *iface)
 {
-    QWindow *window = iface->window();
-    if (!window) {
-        //this is needed to add tabs as the window is not available
-        if (iface->parent()->window()) {
-            window = iface->parent()->window();
-        } else {
-            return emscripten::val::undefined();
-        }
-    }
+    if (!iface)
+        return emscripten::val::undefined();
+    return getContainer(getWindow(iface));
+}
 
-    return getContainer(window);
+QWindow *QWasmAccessibility::getWindow(QAccessibleInterface *iface)
+{
+    QWindow *window = iface->window();
+    // this is needed to add tabs as the window is not available
+    if (!window && iface->parent())
+        window = iface->parent()->window();
+    return window;
 }
 
 emscripten::val QWasmAccessibility::getDocument(const emscripten::val &container)
diff --git a/src/plugins/platforms/wasm/qwasmaccessibility.h b/src/plugins/platforms/wasm/qwasmaccessibility.h
index 73a32d31b7..dd9770179a 100644
--- a/src/plugins/platforms/wasm/qwasmaccessibility.h
+++ b/src/plugins/platforms/wasm/qwasmaccessibility.h
@@ -36,6 +36,7 @@ private:
     static emscripten::val getContainer(QAccessibleInterface *iface);
     static emscripten::val getDocument(const emscripten::val &container);
     static emscripten::val getDocument(QAccessibleInterface *iface);
+    static QWindow *getWindow(QAccessibleInterface *iface);
 
     emscripten::val createHtmlElement(QAccessibleInterface *iface);
     void destroyHtmlElement(QAccessibleInterface *iface);