Initial checkin of a perf test suite for Indexed Database. This just has a

chrome/test/data/indexeddb/perf_shared.js

Index: chrome/test/data/indexeddb/perf_shared.js
diff --git a/chrome/test/data/indexeddb/perf_shared.js b/chrome/test/data/indexeddb/perf_shared.js
new file mode 100644
index 0000000000000000000000000000000000000000..5f6ca6de645afc18ac59d88ec47ed5ae01d5526c
--- /dev/null
+++ b/chrome/test/data/indexeddb/perf_shared.js
@@ -0,0 +1,121 @@
+window.indexedDB = window.indexedDB || window.webkitIndexedDB ||
+    window.mozIndexedDB || window.msIndexedDB;
+window.IDBTransaction = window.IDBTransaction || window.webkitIDBTransaction ||

[jsbell, 2012/06/21 00:04:16]

Shouldn't need to reference IDBTransaction directly any more, so this can be
removed.

[ericu, 2012/07/11 18:04:35]

Removed.

+    window.mozIDBTransaction || window.msIDBTransaction;
+
+var automation = {
+  results: {}
+};
+
+automation.setDone = function() {
+  this.setStatus("Test complete.");
+  document.cookie = '__done=1; path=/';
+};
+
+automation.addResult = function(name, result) {
+  result = "" + result;
+  this.results[name] = result;
+  var elt = document.getElementById('results');
+  var div = document.createElement('div');
+  div.innerText = name + ": " + result;
+  elt.appendChild(div);
+};
+
+automation.getResults = function() {
+  return this.results;
+};
+
+automation.setStatus = function(s) {
+  document.getElementById('status').innerText = s;
+};
+
+function assert(t) {
+  if (!t) {
+    var e = new Error("Assertion failed!");
+    console.log(e.stack);
+    throw e;
+  }
+}
+
+function onError(e) {
+  console.log(e);
+  throw new Error(e);
+}
+
+var version = 2;  // The version with our object stores.
+var db;
+
+function createDatabase(name, objectStores, handler, errorHandler) {
+  var os = objectStores;

[jsbell, 2012/06/21 00:04:16]

What's this extra object reference for?

[ericu, 2012/07/11 18:04:35]

Removed; I was thinking I'd need it to get the closure right, but it turned out
not to be necessary.  I still need to look at things a few times to get closures
right in JS.

+  var openRequest = indexedDB.open(name, version);
+  openRequest.onblocked = errorHandler;
+  function createObjectStores(db) {
+    for (var store in os) {
+      var name = os[store];
+      assert(!db.objectStoreNames.contains(name));
+      db.createObjectStore(name);
+    }
+  }
+  openRequest.onupgradeneeded = function(ev) {
+    // TODO: This is the spec-compliant path, which doesn't yet work in Chrome,
+    // and isn't yet tested, as this function won't currently be called.
+    assert(openRequest == ev.target);
+    db = openRequest.result;
+    createObjectStores(db);
+    // onsuccess will get called after this exits.
+  };
+  openRequest.onsuccess = function(ev) {
+    assert(openRequest == ev.target);
+    db = openRequest.result;
+    db.onerror = function(ev) {
+      console.log("db error", arguments, openRequest.webkitErrorMessage);
+      errorHandler();
+    }
+    if (db.version != version) {
+      // This is the current Chrome path.
+      var setVersionRequest = db.setVersion(version);
+      setVersionRequest.onfailure = errorHandler;
+      setVersionRequest.onsuccess =
+          function(e) {
+            assert(setVersionRequest == e.target);
+            createObjectStores(db);
+            var versionTransaction = setVersionRequest.result;
+            versionTransaction.oncomplete = function() {handler(db); };
+            versionTransaction.onerror = onError;
+          }
+    } else {
+      handler(db);
+    }
+  }
+}
+
+function getTransaction(db, objectStoreNames, mode, opt_handler) {
+  var transaction = db.transaction(objectStoreNames, mode);
+  transaction.onerror = onError;

[jsbell, 2012/06/21 00:04:16]

FYI, transaction.onerror sees errors bubbled up from individual requests which
were not handled/prevented. If the bubbling is not stopped here they hit the
database, and will eventually cause the transaction to abort. Therefore, it may
or may not be worth trapping onerror here. (i.e. may be extra log spam, etc). If
added for general logging, it could be done on the database connection's onerror
instead.

[ericu, 2012/07/11 18:04:35]

I added a stopPropagation in onError.  In generally I'm going to try to err on
the side of verbosity on errors, especially for errors that should never happen
in the tests.  I also want to catch them as early as possible in the
propagation, so as to be able to localize them better, but I haven't put in that
bit yet.

+  transaction.onabort = onError;
+  if (opt_handler) {
+    transaction.oncomplete = opt_handler;
+  }
+  return transaction;
+}
+
+function deleteDatabase(name, opt_handler) {
+  var deleteRequest = indexedDB.deleteDatabase(name);
+  deleteRequest.onerror = onError;
+  if (opt_handler) {
+    deleteRequest.onsuccess = opt_handler;
+  }
+}
+
+function cleanUp(opt_handler) {
+  if (db) {
+    deleteDatabase(db, opt_handler);
+    db = null;
+  }
+}
+
+function stringOfLength(n) {
+  assert(n > 0);
+  assert(n == Math.floor(n));
+  return new Array(n + 1).join('0');
+}