Auto merge of #20150 - upsuper:text-is-significant, r=emilio

Remove text-is-significant param from Gecko_IsSignificantChild

This is Servo side change of [bug 1441729](https://bugzilla.mozilla.org/show_bug.cgi?id=1441729).

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components/style/gecko/generated/bindings.rs

@@ -608,7 +608,6 @@ extern "C" {
 extern "C" {
     pub fn Gecko_IsSignificantChild(
         node: RawGeckoNodeBorrowed,
-        text_is_significant: bool,
         whitespace_is_significant: bool,
     ) -> bool;
 }

components/style/gecko/wrapper.rs

@@ -256,7 +256,7 @@ impl<'ln> GeckoNode<'ln> {
 
     #[inline]
     fn contains_non_whitespace_content(&self) -> bool {
-        unsafe { Gecko_IsSignificantChild(self.0, true, false) }
+        unsafe { Gecko_IsSignificantChild(self.0, false) }
     }
 }
 
@@ -1933,7 +1933,7 @@ impl<'le> ::selectors::Element for GeckoElement<'le> {
 
     fn is_empty(&self) -> bool {
         !self.as_node().dom_children().any(|child| unsafe {
-            Gecko_IsSignificantChild(child.0, true, true)
+            Gecko_IsSignificantChild(child.0, true)
         })
     }