 
 /* Code for drawing the urlbar curve */
 private class CurveView: UIView {
+    private lazy var leftCurvePath: UIBezierPath = {
+        var leftArc = UIBezierPath(arcCenter: CGPoint(x: 5, y: 5), radius: CGFloat(5), startAngle: CGFloat(-M_PI), endAngle: CGFloat(-M_PI_2), clockwise: true)
+        leftArc.addLineToPoint(CGPoint(x: 0, y: 0))
+        leftArc.addLineToPoint(CGPoint(x: 0, y: 5))
+        leftArc.closePath()
+        return leftArc
+    }()
+
     override init(frame: CGRect) {
         super.init(frame: frame)
         commonInit()

            let tabsButtonTransform = CGAffineTransformMakeTranslation(self.tabsButton.frame.width + URLBarViewUX.URLBarCurveOffset, 0)
            self.tabsButton.transform = tabsButtonTransform
            self.clonedTabsButton?.transform = tabsButtonTransform
            self.curveShape.transform = CGAffineTransformMakeTranslation(self.tabsButton.frame.width + URLBarViewUX.URLBarCurveOffset + URLBarViewUX.URLBarCurveBounceBuffer, 0)

            if self.toolbarIsShowing {
                self.backButtonLeftConstraint?.updateOffset(-3 * AppConstants.ToolbarHeight)
            }

            make.trailing.equalTo(self)
            make.width.height.equalTo(AppConstants.ToolbarHeight)
        }
        updateLayoutForEditing(editing: isEditing, animated: false)
        super.updateConstraints()
    }
