[turbolizer] Factor out some user actions into methods of GraphView.

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;
 }
+
+// Partial application without binding the receiver
+function partial(f) {
+  var arguments1 = Array.prototype.slice.call(arguments, 1);
+  return function() {
+    var arguments2 = Array.from(arguments);
+    f.apply(this, arguments1.concat(arguments2));
+  }
+}