[WebApp] Mobile platform browser resolution adaptation

Make WebApp fit n multi-browser, remember the browser encountered the need to pay attention to the place.

Firefox is currently found to be the most difficult to match.

1.firefox the correct innerwidth value can only be taken after the onload.

2. The current version of Firefox can not set the width of viewport, regardless of the number of written, always 360. Estimate does not write viewport, is 980.

Then is the Qq browser, seems to be unable to set viewport, but QQ browser unexpectedly support target-densitydpi.

and Safari. This is the egg that hurts the most. Because only a little bit of space on the 4s can be used.

[WebApp] Mobile platform browser resolution adaptation