Fabric update new canvas, new jsdom

[asturur]

• update jsdom to 13
• update canvas to 2
• remove node 4 and 6
• remove xmldom since JSDOM now parses XMLs too
• update test to take care of how JSDOM request resources now
• update visual test loop to create a new canvas and dispose it each test
• update visual test code to do not use the requestRenderCallback
• added NODE 11 to test matrix
• removed allowed failures, since today all test have to pass in node as in browser
• swapped istanbul with nyc
• updated qunit to latest 2.9.2

[danielbeardsley]

Canvas 2.0 has some breaking changes

[asturur]

i know i know, did not read yet how to interact with new jsdom. Canvas is transparent for us

[Rosga]

This is how I use canvas@2.3.1 and jsdom@13.2.0 in my project based an fabric.

const jsdom = require('jsdom');
const virtualWindow = new jsdom.JSDOM(
  decodeURIComponent('%3C!DOCTYPE%20html%3E%3Chtml%3E%3Chead%3E%3C%2Fhead%3E%3Cbody%3E%3C%2Fbody%3E%3C%2Fhtml%3E'),
  {
    features: {
      FetchExternalResources: ['img']
    },
    resources: "usable"
  }).window;
fabric.document = virtualWindow.document;
fabric.jsdomImplForWrapper = require('jsdom/lib/jsdom/living/generated/utils').implForWrapper;
fabric.nodeCanvas = require('jsdom/lib/jsdom/utils').Canvas;
fabric.window = virtualWindow;
if (typeof DOMParser === "undefined") {
  global.DOMParser = null;
}
DOMParser = require('xmldom').DOMParser;

[asturur]

why you do not open a pr, so i can close this?

[asturur]

So far so good, we are currently stopped by jsdom/jsdom#2503

If they fix this bug, we can migrate.

[asturur]

moved to jsdom 13.1
This could allow us to move forward.

[asturur]

ok we have a green build but node tests ( previously marked as possibly fail ) fail harder than before.
I would like to keep the same level of confidence, so just need a little more look.