wasm test suite (#1116)

* wasm: add test suite using headlless chrome

tests/wasm/testdata/chan.go

@@ -0,0 +1,16 @@
+package main
+
+func main() {
+
+	ch := make(chan bool, 1)
+	println("1")
+	go func() {
+		println("2")
+		ch <- true
+		println("3")
+	}()
+	println("4")
+	v := <-ch
+	println(v)
+
+}