Auto merge of #20674 - simartin:issue_20556, r=nox

Issue #20556: Implement proper checks in WebGLRenderingContext's bindBuffer()

Implement missing check, about deleted buffers.
---
- [X] `./mach build -d` does not report any errors
- [X] `./mach build-geckolib` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #20556
- [X] There are tests for these changes

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tests/wpt/mozilla/meta/MANIFEST.json

@@ -39217,6 +39217,12 @@
      {}
     ]
    ],
+   "mozilla/webgl/bindBuffer.html": [
+    [
+     "/_mozilla/mozilla/webgl/bindBuffer.html",
+     {}
+    ]
+   ],
    "mozilla/webgl/bufferData.html": [
     [
      "/_mozilla/mozilla/webgl/bufferData.html",
@@ -70856,6 +70862,10 @@
    "bc2a964c294e678b3c0e98ba83ce30a59a8bee3f",
    "testharness"
   ],
+  "mozilla/webgl/bindBuffer.html": [
+   "659d53041373a6e40b9ab4cbf7e2afad45048377",
+   "testharness"
+  ],
   "mozilla/webgl/bufferData.html": [
    "e58b2257043682723fbd17eac6dcbadb32c3ca3e",
    "testharness"