Output pop up shown twice on iPad for procedure testing

[MNSDivya]

Describe the bug
Output pop up shown twice on iPad for procedure testing

To Reproduce

Steps to reproduce the behavior:
Build the above set of blocks on the empty playground by selecting " categories(untyped variables)"
https://screenshot.googleplex.com/Y8TsM31vvqo.png

1.Export the blocks to xml
2.Clear the workspace
3.Import the xml you just exported
4.Verify the blocks are the same as above
5.Copy the XML from the text area
6.Paste it into the XML tab on the Blockly code demo(https://google.github.io/blockly/demos/code/index.html)
7.Click the red play button in the upper right corner

Expected behavior
Verify you get a popup that prints the value 10.

Actual behavior
Value pop up 10 is shown twice.

Smartphone (please complete the following information):

• Device: iPad Model A1566
• Browser: safari

Please note that it is working fine on desktop version with chrome and firefox browsers.

[samelhusseini]

Thanks for filing, this is a dupe of #1949