Add offscreen-canvas to the list of wpt directories to skip.

third_party/WebKit/LayoutTests/imported/wpt/offscreen-canvas/drawing-images-to-the-canvas/2d.drawImage.negativedest.worker.js

-// DO NOT EDIT! This test has been generated by tools/gentest.py.
-// OffscreenCanvas test in a worker:2d.drawImage.negativedest
-// Description:Negative destination width/height represents the correct rectangle
-// Note:
-
-importScripts("/resources/testharness.js");
-importScripts("/common/canvas-tests.js");
-
-var t = async_test("Negative destination width/height represents the correct rectangle");
-t.step(function() {
-
-var offscreenCanvas = new OffscreenCanvas(100, 50);
-var ctx = offscreenCanvas.getContext('2d');
-
-ctx.fillStyle = '#f00';
-ctx.fillRect(0, 0, 100, 50);
-var promise = new Promise(function(resolve, reject) {
-    var xhr = new XMLHttpRequest();
-    xhr.open("GET", '/images/ggrr-256x256.png');
-    xhr.responseType = 'blob';
-    xhr.send();
-    xhr.onload = function() {
-        resolve(xhr.response);
-    };
-});
-promise.then(function(response) {
-    ctx.drawImage(response, 100, 78, 50, 50, 0, 50, 50, -50);
-    ctx.drawImage(response, 100, 128, 50, -50, 100, 50, -50, -50);
-    _assertPixelApprox(offscreenCanvas, 1,1, 0,255,0,255, "1,1", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 1,48, 0,255,0,255, "1,48", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 98,1, 0,255,0,255, "98,1", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 98,48, 0,255,0,255, "98,48", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 48,1, 0,255,0,255, "48,1", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 48,48, 0,255,0,255, "48,48", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 51,1, 0,255,0,255, "51,1", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 51,48, 0,255,0,255, "51,48", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 25,25, 0,255,0,255, "25,25", "0,255,0,255", 2);
-    _assertPixelApprox(offscreenCanvas, 75,25, 0,255,0,255, "75,25", "0,255,0,255", 2);
-});
-
-t.done();
-
-});
-done();