IDB: Layout test showing ro transactions wait for rw transactions

LayoutTests/storage/indexeddb/resources/transaction-coordination-ro-waits-for-rw.js

Index: LayoutTests/storage/indexeddb/resources/transaction-coordination-ro-waits-for-rw.js
diff --git a/LayoutTests/storage/indexeddb/resources/transaction-coordination-ro-waits-for-rw.js b/LayoutTests/storage/indexeddb/resources/transaction-coordination-ro-waits-for-rw.js
new file mode 100644
index 0000000000000000000000000000000000000000..afcaf61b902f345b3a24bc358a4f7a7be470b111
--- /dev/null
+++ b/LayoutTests/storage/indexeddb/resources/transaction-coordination-ro-waits-for-rw.js
@@ -0,0 +1,38 @@
+if (this.importScripts) {
+    importScripts('../../../resources/js-test.js');
+    importScripts('shared.js');
+}
+
+description("readonly transaction should see the result of a previous readwrite transaction");
+
+indexedDBTest(prepareDatabase, runTransactions);
+
+function prepareDatabase(evt)
+{
+    preamble(evt);
+    evalAndLog("db = event.target.result");
+    evalAndLog("store = db.createObjectStore('store')");
+    evalAndLog("store.put('original value', 'key')");
+}
+
+function runTransactions(evt)
+{
+    preamble(evt);
+    evalAndLog("db = event.target.result");
+    evalAndLog("transaction1 = db.transaction('store', 'readwrite')");
+    transaction1.onabort = unexpectedAbortCallback;
+    evalAndLog("transaction2 = db.transaction('store', 'readonly')");
+    transaction2.onabort = unexpectedAbortCallback;
+
+    evalAndLog("request = transaction1.objectStore('store').put('new value', 'key')");
+    request.onerror = unexpectedErrorCallback;
+
+    evalAndLog("request2 = transaction2.objectStore('store').get('key')");
+    request2.onerror = unexpectedErrorCallback;
+    request2.onsuccess = function checkResult(evt) {
+        preamble(evt);
+        shouldBeEqualToString('request2.result', 'new value');
+        db.close();
+        finishJSTest();
+    };
+}