Add a warning for the deprecation of content-initiated data URL navigations

third_party/WebKit/LayoutTests/fast/loader/reload-zero-byte-plugin.html

+<iframe src="data:application/x-blink-test-plugin," id="f"></iframe>

[Charlie Reis, 2017/02/23 18:39:13]

Interesting.  I guess this is close enough that it should be testing the same
thing.

[meacer, 2017/02/23 20:47:25]

I was slightly concerned too, but the plugin prints a string and the test
outputs are still the same so it seemed okay to me to do this.

 <script>
 if (window.testRunner) {
     testRunner.dumpAsText();
     testRunner.waitUntilDone();
     testRunner.setCanOpenWindows(true);
     testRunner.setCloseRemainingWindowsWhenComplete(true);
 }
 
-var win = window.open('data:application/x-blink-test-plugin,');
 setTimeout(function() {
-    win.location.reload();
+    document.getElementById("f").contentWindow.location.reload()
     setTimeout(function() {
         if (window.testRunner)
             testRunner.notifyDone();
     }, 100);
 }, 100);
 </script>
 This test passes if it doesn't crash. To run manually, please disable your
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