Auto merge of #12159 - notriddle:fix_interpolate_cleanup_regression, r=emilio

Do not crash on partial calc interpolation

It should always be possible to interpolate between CalcLengthOrPercentage points.
____

- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #12151 (github issue number if applicable).
- [ ] There are tests for these changes  (*I STILL NEED TO WRITE TESTS*)

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components/style/properties/helpers/animated_properties.mako.rs

@@ -324,8 +324,8 @@ impl Interpolate for CalcLengthOrPercentage {
     #[inline]
     fn interpolate(&self, other: &Self, time: f64) -> Result<Self, ()> {
         Ok(CalcLengthOrPercentage {
-            length: try!(self.length.interpolate(&other.length, time)),
-            percentage: try!(self.percentage.interpolate(&other.percentage, time)),
+            length: self.length.interpolate(&other.length, time).ok().and_then(|x|x),
+            percentage: self.percentage.interpolate(&other.percentage, time).ok().and_then(|x|x),
         })
     }
 }