Typecheck chrome://help using CompilerPass.java, everything except dependency to options

ui/webui/resources/js/assert.js

Index: ui/webui/resources/js/assert.js
diff --git a/ui/webui/resources/js/assert.js b/ui/webui/resources/js/assert.js
index 7b38398ed0175179cfc6efaf510b489a73bbf591..563b12ec4bfe63b4dc6815e8d1c5cb706581aaf4 100644
--- a/ui/webui/resources/js/assert.js
+++ b/ui/webui/resources/js/assert.js
@@ -47,3 +47,16 @@ function assert(condition, opt_message) {
 function assertNotReached(opt_message) {
   throw new Error(opt_message || "Unreachable code hit");
 }
+
+/**
+ * @param {*} value The value to check.
+ * @param {function(new: T, ...)} type A user-defined constructor.
+ * @return {!T}
+ * @template T
+ */
+function assertInstanceof(value, type) {
+  if (!(value instanceof type)) {

[Dan Beam, 2014/08/13 22:20:08]

nit: no curlies

[Vitaly Pavlenko, 2014/08/14 00:01:02]

Done.

+    throw new Error('assertInstanceof');

[Dan Beam, 2014/08/13 22:20:07]

throw new Error(value + ' is not a[n] ' + (type.name || typeof type));

[Vitaly Pavlenko, 2014/08/14 00:01:02]

Done.

+  }
+  return value;
+}