Auto merge of #13324 - anholt:webgl-default-texture, r=jdm

Update offscreen_gl_context dependency to get webgl fix.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #11618

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tests/wpt/metadata/webgl/conformance-1.0.3/conformance/textures/default-texture.html.ini

@@ -1,11 +0,0 @@
-[default-texture.html]
-  type: testharness
-  [WebGL test #0: successfullyParsed should be true (of type boolean). Was undefined (of type undefined).]
-    expected: FAIL
-
-  [WebGL test #0: at (0, 0) expected: 0,0,0,255 was 0,0,0,0]
-    expected: FAIL
-
-  [WebGL test #0: at (0, 0) expected: 0,0,0,255 was 64,255,191,128]
-    expected: FAIL
-