IndexedDB: Align abort behavior on uncaught exception with Gecko

third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js

Index: third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js
diff --git a/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js b/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js
index 63b23e5a73e7af363dd50a9cf407ffb04bc53f8d..9119d828e836ea55ad8f4c1c071a45f652222998 100644
--- a/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js
+++ b/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js
@@ -143,3 +143,21 @@ function expect(t, expected) {
     }
   };
 }
+
+// Checks to see if the passed transaction is active (by making
+// requests against the named store).
+function is_transaction_active(tx, store_name) {
+  try {
+    const request = tx.objectStore(store_name).get(0);
+    request.onerror = e => {
+      e.preventDefault();
+      e.stopPropagation();
+    };
+    return true;
+  } catch (ex) {
+    assert_equals(ex.name, 'TransactionInactiveError',
+                  'Active check should either not throw anything, or throw ' +
+                  'TransactionInactiveError');
+    return false;
+  }
+}