[turbolizer] Add 2 buttons; add middle-click on input; add comment in UI.

tools/turbolizer/util.js

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 "use strict";
 
 function makeContainerPosVisible(container, pos) {
   var height = container.offsetHeight;
   var margin = Math.floor(height / 4);
   if (pos < container.scrollTop + margin) {
@@ skipping 51 matching lines @@
 function sortUnique(arr, f) {
   arr = arr.sort(f);
   let ret = [arr[0]];
   for (var i = 1; i < arr.length; i++) {
     if (arr[i-1] !== arr[i]) {
       ret.push(arr[i]);
     }
   }
   return ret;
 }
+
+// Find elements in the array that match a filter. Apply an action on each
+// such element. Check if new elements match the filter; apply the action to
+// those elements. Repeat until no new elements match the filter and the
+// action has been called at least once on elements that match the filter.
+//
+// The filter should not have any side effects. Any elements that match the
+// filter should continue to match the filter, regardless of calls to the
+// action on arbitrary elements.
+//
+// Returns nothing.
+function filterActionUntilStabilize(arr, filt, action) {
+
+  var elementsLeft = arr.slice(); // shallow copy
+
+  while (true) {
+    var matching = [];
+    var nonMatching = [];
+
+    elementsLeft.forEach(function(element) {
+      if (filt(element)) {
+        matching.push(element);
+        action(element);
+      } else {
+        nonMatching.push(element);
+      }
+    });
+
+    if (elementsLeft.length == nonMatching.length) {
+      // We stabilized; exit.
+      break;
+    } else {
+      // Some elements matched and we called the action. It is possible that
+      // elements that never matched the filter, will match it on the next
+      // iteration.
+      elementsLeft = nonMatching;
+      continue;
+    }
+  }
+}