Auto merge of #25710 - pylbrecht:pattern.incomplete, r=jdm

Make CanvasRenderingContext2D.createPattern() return null for incomplete images

<!-- Please describe your changes on the following line: -->
`createPattern()` should return `null` if the passed `image` argument is not usable.

References:
- https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-createpattern
- https://html.spec.whatwg.org/multipage/canvas.html#check-the-usability-of-the-image-argument
---
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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 part of #25331

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- [x] There are tests for these changes

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tests/wpt/metadata/2dcontext/fill-and-stroke-styles/2d.pattern.image.broken.html.ini

@@ -0,0 +1,5 @@
+[2d.pattern.image.broken.html]
+  type: testharness
+  [Canvas test: 2d.pattern.image.broken]
+    expected: FAIL
+

tests/wpt/metadata/2dcontext/fill-and-stroke-styles/2d.pattern.image.incomplete.emptysrc.html.ini

@@ -1,5 +0,0 @@
-[2d.pattern.image.incomplete.emptysrc.html]
-  type: testharness
-  [Canvas test: 2d.pattern.image.incomplete.emptysrc]
-    expected: FAIL
-

tests/wpt/metadata/2dcontext/fill-and-stroke-styles/2d.pattern.image.incomplete.immediate.html.ini

@@ -1,5 +0,0 @@
-[2d.pattern.image.incomplete.immediate.html]
-  type: testharness
-  [Canvas test: 2d.pattern.image.incomplete.immediate]
-    expected: FAIL
-

tests/wpt/metadata/2dcontext/fill-and-stroke-styles/2d.pattern.image.incomplete.nosrc.html.ini

@@ -1,5 +0,0 @@
-[2d.pattern.image.incomplete.nosrc.html]
-  type: testharness
-  [Canvas test: 2d.pattern.image.incomplete.nosrc]
-    expected: FAIL
-

tests/wpt/metadata/2dcontext/fill-and-stroke-styles/2d.pattern.image.incomplete.reload.html.ini

@@ -1,5 +0,0 @@
-[2d.pattern.image.incomplete.reload.html]
-  type: testharness
-  [Canvas test: 2d.pattern.image.incomplete.reload]
-    expected: FAIL
-

tests/wpt/metadata/2dcontext/fill-and-stroke-styles/2d.pattern.image.incomplete.removedsrc.html.ini

@@ -1,5 +0,0 @@
-[2d.pattern.image.incomplete.removedsrc.html]
-  type: testharness
-  [Canvas test: 2d.pattern.image.incomplete.removedsrc]
-    expected: FAIL
-