Auto merge of #15294 - atheed:unused-import-fix, r=Manishearth

Removed unused import

Removed an unused import in `components/script/dom/element.rs`.

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components/script/dom/element.rs

@@ -109,7 +109,7 @@ use style::selector_parser::{NonTSPseudoClass, RestyleDamage, SelectorImpl, Sele
 use style::sink::Push;
 use style::stylist::ApplicableDeclarationBlock;
 use style::values::CSSFloat;
-use style::values::specified::{self, CSSColor, CSSRGBA, LengthOrPercentage};
+use style::values::specified::{self, CSSColor, CSSRGBA};
 use stylesheet_loader::StylesheetOwner;
 
 // TODO: Update focus state when the top-level browsing context gains or loses system focus,