Auto merge of #16829 - hiikezoe:disallow-negative-duration, r=emilio

Disallow negative duration for animation and transition

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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 #15343

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- [X] There are tests for these changes written by @simon-whitehead . Thank you!

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tests/wpt/metadata-css/css-transitions-1_dev/html/transition-duration-001.htm.ini

@@ -1,8 +0,0 @@
-[transition-duration-001.htm]
-  type: testharness
-  [parse '-5s']
-    expected: FAIL
-
-  [parse '-500ms']
-    expected: FAIL
-

tests/wpt/metadata-css/css-values-3_dev/html/transition-duration-001.htm.ini

@@ -1,8 +0,0 @@
-[transition-duration-001.htm]
-  type: testharness
-  [parse '-5s']
-    expected: FAIL
-
-  [parse '-500ms']
-    expected: FAIL
-