Auto merge of #24626 - glowe:issue-21810/improve-validation-methods, r=jdm

Issue 21810/improve validation methods

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This is a start at addressing #21810. I'm putting these changes out early to get some feedback on the following items:

1. I added unit tests for the validation methods mentioned in #21810, because I couldn't tell whether any of the existing WPT tests covered them. Are these tests worthwhile? Are any of them unnecessary?
2. I changed the implementation for `is_valid_floating_point_number_string` so that it passed the tests. The previous version of the function wasn't restrictive enough (it allowed certain whitespace characters before the number string).
3. I changed the catch-all condition in `htmlinputelement.rs` to account for the remaining input types that don't have a value sanitization algorithm. This last change seems good to me since we won't be able to add a new input type without adding it to the case and checking the spec for an algorithm.
---
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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 #21810

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- [x] There are tests for these changes

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tests/wpt/metadata/MANIFEST.json

@@ -659568,7 +659568,7 @@
    "testharness"
   ],
   "html/semantics/forms/the-input-element/number.html": [
-   "64868f02efca707cfe88a51e9bd91574dfbcaad9",
+   "7d93f208985d305d46324d0ecf34e8c4ff2ad361",
    "testharness"
   ],
   "html/semantics/forms/the-input-element/password.html": [

tests/wpt/web-platform-tests/html/semantics/forms/the-input-element/number.html

@@ -35,7 +35,11 @@
     {value: "+1", expected: "", testname: "value = +1"},
     {value: "+", expected: "", testname: "value = '+'"},
     {value: "-", expected: "", testname: "value = '-'"},
-    {value: " 1", expected: "", testname: "value with a leading whitespace"},
+    {value: "\t1", expected: "", testname: "value with a leading tab"},
+    {value: "\n1", expected: "", testname: "value with a leading newline"},
+    {value: "\f1", expected: "", testname: "value with a leading form feed"},
+    {value: "\r1", expected: "", testname: "value with a leading carriage return"},
+    {value: " 1", expected: "", testname: "value with a leading space"},
     {value: "1trailing junk", expected: "", testname: "value = 1trailing junk"}
   ];
   for (var i = 0; i < numbers.length; i++) {