Auto merge of #19970 - janczer:change_debug_assertions, r=emilio

Change debug assertions to specific ones

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---
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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 #19962 (github issue number if applicable).

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components/script/dom/characterdata.rs

@@ -291,7 +291,7 @@ fn split_at_utf16_code_unit_offset(s: &str, offset: u32) -> Result<(&str, Option
         if c > '\u{FFFF}' {
             if code_units == offset {
                 if opts::get().replace_surrogates {
-                    debug_assert!(c.len_utf8() == 4);
+                    debug_assert_eq!(c.len_utf8(), 4);
                     return Ok((&s[..i], Some(c), &s[i + c.len_utf8()..]))
                 }
                 panic!("\n\n\

components/script/dom/node.rs

@@ -1334,7 +1334,7 @@ impl TreeIterator {
             }
             self.depth -= 1;
         }
-        debug_assert!(self.depth == 0);
+        debug_assert_eq!(self.depth, 0);
         self.current = None;
         Some(current)
     }

components/script/dom/webgltexture.rs

@@ -313,7 +313,7 @@ impl WebGLTexture {
     }
 
     fn is_cube_complete(&self) -> bool {
-        debug_assert!(self.face_count.get() == 6);
+        debug_assert_eq!(self.face_count.get(), 6);
 
         let image_info = self.base_image_info().unwrap();
         if !image_info.is_defined() {