Describe the bug:

Tapping on a number in the stock android keyboard results in two numbers being entered into the widget.Entry

To Reproduce:

Steps to reproduce the behaviour:

1. Install fyne_demo
2. Click on Widgets -> Text
3. Tap Entry and insert numeric info
4. See error

Screen capture:

https://gophers.slack.com/archives/CB4QUBXGQ/p1598039652090300 (Github doesn't support uploading mp4)

Device (please complete the following information):

• OS: Android
• Version: 10
• Go version: go1.15 darwin/amd64
• Fyne version: 6c9ed1b