Auto merge of #19007 - MortimerGoro:const_codegen, r=emilio

Fix Const IDL value compilation errors in codegen

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I found that some const WebIDL values fail at rust compile time.

Example:

const long long TIMEOUT_IGNORED  = -1;

```
906 |     ConstantSpec { name: b"TIMEOUT_IGNORED\0", value: ConstantVal::DoubleVal(-1) }]
    |                                                                              ^^ expected f64, found integral variable
    |
    = note: expected type `f64`
               found type `{integer}`
```

I added a explicit cast to to fix the problem in conversions that may fail to compile.

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- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

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components/script/dom/webidls/TestBinding.webidl

@@ -151,6 +151,13 @@ interface TestBinding {
   [BinaryName="BinaryRenamedAttribute2"] attribute DOMString attr-to-binary-rename;
   attribute DOMString attr-to-automatically-rename;
 
+  const long long constantInt64 = -1;
+  const unsigned long long constantUint64 = 1;
+  const float constantFloat32 = 1.0;
+  const double constantFloat64 = 1.0;
+  const unrestricted float constantUnrestrictedFloat32 = 1.0;
+  const unrestricted double constantUnrestrictedFloat64 = 1.0;
+
   [PutForwards=booleanAttribute]
   readonly attribute TestBinding forwardedAttribute;