The required canvas configuration is an implementation
detail; move it out of the .html file (which we expect
that users will replace), and into the QWasmScreen
constructor.
This also enables using a div element as the container
element (instead of a canvas), since Qt then can create
and configure the canvas during QWasmScreen construction.
Change-Id: Ia849517d00fa3e8ec307065a524c0c91296dd490
Reviewed-by: Lorn Potter <lorn.potter@gmail.com>
2ed3cc8e7a