SSO login: Fix webview

[marczych]

I'm not sure what exactly what caused the issue, but the WebView used to display OpenID/SSO login wasn't displaying any content.

I think it was ultimately a combination of the following:

• Upgrading to 4.4 which uses Chrome for the default WebView client
• Loading pages with insecure content
• Layout width
• Overriding the WebChromeClient
• Not specifying a wide viewport

At any rate, this code is more consistent with the other WebView we use for displaying Answers and no longer exhibits any of the aforementioned problems.

[timothyasp]

Looks fine, if you think removing the progress from the web view looks better then CR :+1: