Update WebGL tests

This brings in https://github.com/KhronosGroup/WebGL/pull/2708.

tests/wpt/webgl/meta/MANIFEST.json

@@ -36364,7 +36364,7 @@
    "testharness"
   ],
   "conformance/rendering/framebuffer-switch.html": [
-   "943f571b3b15f9794e2a9e3f89fcdadf1d49b6dd",
+   "fc8c3dc5dac8a2ece2b286325bf8f1b227f3aee6",
    "testharness"
   ],
   "conformance/rendering/framebuffer-texture-clear.html": [
@@ -36372,7 +36372,7 @@
    "testharness"
   ],
   "conformance/rendering/framebuffer-texture-switch.html": [
-   "5b677f79ad9378638624dab7c001f8381eed5e87",
+   "04d03a0bc2e2f834762f0bb47e484a38323213f8",
    "testharness"
   ],
   "conformance/rendering/gl-clear.html": [

tests/wpt/webgl/meta/conformance/rendering/framebuffer-switch.html.ini

@@ -1,3 +0,0 @@
-[framebuffer-switch.html]
-  bug: https://github.com/servo/servo/issues/8984
-  expected: ERROR

tests/wpt/webgl/meta/conformance/rendering/framebuffer-texture-switch.html.ini

@@ -1,3 +0,0 @@
-[framebuffer-texture-switch.html]
-  bug: https://github.com/servo/servo/issues/8984
-  expected: ERROR

tests/wpt/webgl/tests/conformance/rendering/framebuffer-switch.html

@@ -44,6 +44,7 @@
 "use strict";
 description("Test framebuffer switching. The test switches between two framebuffers, copying rendering results from one to the other.");
 var wtu = WebGLTestUtils;
+var canvas = document.getElementById("canvas");
 
 var gl = wtu.create3DContext("canvas");
 var program = wtu.setupTexturedQuad(gl);

tests/wpt/webgl/tests/conformance/rendering/framebuffer-texture-switch.html

@@ -44,6 +44,7 @@
 "use strict";
 description("Test framebuffer texture attachment switching. The test uses one framebuffer object and switches its color attachment.");
 var wtu = WebGLTestUtils;
+var canvas = document.getElementById("canvas");
 
 var gl = wtu.create3DContext("canvas");
 var program = wtu.setupTexturedQuad(gl);