Fix tooltip occasionally not hiding when using a hide delay

Fixes #14375.
Closes #14519 by merging it.

js/tests/unit/tooltip.js

@@ -928,6 +928,36 @@ $(function () {
     $tooltip.trigger('mouseenter')
   })
 
+  test('should hide tip after hide delay even if moused left before end of fade in', function () {
+    stop()
+
+    var $tooltip = $('<a href="#" rel="tooltip" title="Another tooltip for test"/>')
+      .appendTo('#qunit-fixture')
+      .bootstrapTooltip({ delay: { show: 10, hide: 10 }})
+
+    setTimeout(function () {
+      ok(!$tooltip.data('bs.tooltip').$tip, '1ms: tooltip exists')
+
+      setTimeout(function () {
+        ok($tooltip.data('bs.tooltip').$tip.is('.fade.in'), '10ms: tooltip faded in')
+      }, 10)
+
+      setTimeout(function () {
+        ok($tooltip.data('bs.tooltip').$tip.is('.fade.in'), '15ms: tooltip faded in')
+
+        $tooltip.trigger('mouseout')
+      }, 15)
+
+      setTimeout(function () {
+        ok(!$tooltip.data('bs.tooltip').$tip.is('.fade.in'), '30ms: tooltip faded out')
+
+        start()
+      }, 30)
+    }, 0)
+
+    $tooltip.trigger('mouseenter')
+  })
+
   test('should correctly position tooltips on SVG elements', function () {
     if (!window.SVGElement) {
       // Skip IE8 since it doesn't support SVG