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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components/script/dom/htmlinputelement.rs

@@ -1213,7 +1213,16 @@ impl HTMLInputElement {
                     value.push_str(sanitized.as_str());
                 }
             },
-            _ => (),
+            // The following inputs don't have a value sanitization algorithm.
+            // See https://html.spec.whatwg.org/multipage/#value-sanitization-algorithm
+            InputType::Button |
+            InputType::Checkbox |
+            InputType::File |
+            InputType::Hidden |
+            InputType::Image |
+            InputType::Radio |
+            InputType::Reset |
+            InputType::Submit => (),
         }
     }