[DatePicker] Inline dialog doesn't (re)appear on Android (Chrome)

[iryan2]

Problem description

Once the inline DatePicker's dialog is dismissed, reopening it is difficult and frustrating.

Steps to reproduce

Visit http://www.material-ui.com/#/components/date-picker in Chrome on Android.
Scroll to the inline dialog examples.
Tap the text input.
If the dialog appears, dismiss it.
At this point, it's difficult to open the dialog again. Sometimes a single tap works, but most of the time nothing happens.
Long pressing seems to work reliably but that's not an intuitive way of opening the dialog.

Versions

• Material-UI: 15.2.0
• React: 15.3.1
• Browser: Chrome 52.0.2743.98 on Android 6.0.1

[oliviertassinari]

Closing for #4787