Auto merge of #10516 - Ms2ger:cleanup, r=nox

Various cleanup.

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1 files changed, 11 insertions, 25 deletions

diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 99648369357..748b7b8249e 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -1166,34 +1166,20 @@ impl Iterator for PrecedingNodeIterator {
             Some(current) => current,
         };
 
-        if self.root == current {
-            self.current = None;
-            return None
-        }
-
-        let node = current;
-        if let Some(previous_sibling) = node.GetPreviousSibling() {
+        self.current = if self.root == current {
+            None
+        } else if let Some(previous_sibling) = current.GetPreviousSibling() {
             if self.root == previous_sibling {
-                self.current = None;
-                return None
-            }
-
-            if let Some(last_child) = previous_sibling.descending_last_children().last() {
-                self.current = Some(last_child);
-                return previous_sibling.descending_last_children().last()
+                None
+            } else if let Some(last_child) = previous_sibling.descending_last_children().last() {
+                Some(last_child)
+            } else {
+                Some(previous_sibling)
             }
-
-            self.current = Some(previous_sibling);
-            return node.GetPreviousSibling()
+        } else {
+            current.GetParentNode()
         };
-
-        if let Some(parent_node) = node.GetParentNode() {
-            self.current = Some(parent_node);
-            return node.GetParentNode()
-        }
-
-        self.current = None;
-        None
+        self.current.clone()
     }
 }