Remove focus defocus revert

src/api.focus.js

 c3_chart_fn.focus = function (targetIds) {
-    var $$ = this.internal, candidates;
-
-    targetIds = $$.mapToTargetIds(targetIds);
-    candidates = $$.svg.selectAll($$.selectorTargets(targetIds.filter($$.isTargetToShow, $$))),
-
-    this.revert();
-    this.defocus();
-    candidates.classed(CLASS.focused, true).classed(CLASS.defocused, false);
-    if ($$.hasArcType()) {
-        $$.expandArc(targetIds);
-    }
-    $$.toggleFocusLegend(targetIds, true);
-
-    $$.focusedTargetIds = targetIds;
-    $$.defocusedTargetIds = $$.defocusedTargetIds.filter(function (id) {
-        return targetIds.indexOf(id) < 0;
-    });
 };
 
 c3_chart_fn.defocus = function (targetIds) {
-    var $$ = this.internal, candidates;
-
-    targetIds = $$.mapToTargetIds(targetIds);
-    candidates = $$.svg.selectAll($$.selectorTargets(targetIds.filter($$.isTargetToShow, $$))),
-
-    this.revert();
-    candidates.classed(CLASS.focused, false).classed(CLASS.defocused, true);
-    if ($$.hasArcType()) {
-        $$.unexpandArc(targetIds);
-    }
-    $$.toggleFocusLegend(targetIds, false);
-
-    $$.focusedTargetIds = $$.focusedTargetIds.filter(function (id) {
-        return targetIds.indexOf(id) < 0;
-    });
-    $$.defocusedTargetIds = targetIds;
 };
 
 c3_chart_fn.revert = function (targetIds) {
-    var $$ = this.internal, candidates;
-
-    targetIds = $$.mapToTargetIds(targetIds);
-    candidates = $$.svg.selectAll($$.selectorTargets(targetIds)); // should be for all targets
-
-    candidates.classed(CLASS.focused, false).classed(CLASS.defocused, false);
-    if ($$.hasArcType()) {
-        $$.unexpandArc(targetIds);
-    }
-    if ($$.config.legend_show) {
-        $$.showLegend(targetIds.filter($$.isLegendToShow.bind($$)));
-    }
-
-    $$.focusedTargetIds = [];
-    $$.defocusedTargetIds = [];
 };