Auto merge of #11665 - davideGiovannini:master, r=KiChjang

Fixed issue #11651 (Do not fire a blur event when calling .focus() on…

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Added check in `HTMLElement.Focus` to avoid requesting focus when the element already has it.
Added check in `Document.commit_focus_transaction` to avoid sending `blur` and `focus` events when clicking on an already focused element.

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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 #11651

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script/dom/document.rs

@@ -599,6 +599,9 @@ impl Document {
     /// Reassign the focus context to the element that last requested focus during this
     /// transaction, or none if no elements requested it.
     pub fn commit_focus_transaction(&self, focus_type: FocusType) {
+        if self.focused == self.possibly_focused.get().r() {
+            return
+        }
         if let Some(ref elem) = self.focused.get() {
             let node = elem.upcast::<Node>();
             elem.set_focus_state(false);