LayoutTests/webgl/max-active-contexts-console-warning.html

<script>
// Tests that we log a warning to the console once we attempt to create a context and we passed the limit.
if (window.testRunner)
    testRunner.dumpAsText();

var maxNumberOfActiveContexts = 16;
var contexts = [];
for (var i = 0; i <= maxNumberOfActiveContexts; i++)
    contexts[i] = document.createElement("canvas").getContext("webgl");

</script>