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..20c26f00c26438cdd337574d5cc8b69c7bbf83cb 100644
--- a/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js
+++ b/third_party/WebKit/LayoutTests/external/wpt/IndexedDB/support.js
@@ -143,3 +143,23 @@ function expect(t, expected) {
     }
   };
 }
+
+// Checks to see if the passed transaction is active (by
+// making
+// requests against the named store). Returns a function to
+// to let the transaction finish.

[pwnall, 2017/03/04 00:27:33]

double "to", and I don't think this comment is accurate

[jsbell, 2017/03/06 18:25:02]

Thanks. And whoah, not sure what happened there.

+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, or throw ' +

[pwnall, 2017/03/04 00:27:33]

"not throw anything" would make the structure parallel with "should throw ...",
and is a bit easier to parse for me.

[jsbell, 2017/03/06 18:25:02]

Done.

+                  'TransactionInactiveError');
+    return false;
+  }
+}