Devtools: Fix "unable to change the value of R/G/B/A" in color picker

Source/devtools/front_end/elements/Spectrum.js

 /*
  * Copyright (C) 2011 Brian Grinstead All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 295 matching lines @@
     {
         /**
          * @param {!Element} element
          * @return {string}
          */
         function elementValue(element)
         {
             return element.value;
         }
 
-        var element = /** @type {!Element} */(event.currentTarget);
-        WebInspector.handleElementValueModifications(event, element);
+        var inputElement = /** @type {!Element} */(event.currentTarget);
+        var arrowKeyOrMouseWheelEvent = (event.keyIdentifier === "Up" || event.keyIdentifier === "Down" || event.type === "mousewheel");
+        var pageKeyPressed = (event.keyIdentifier === "PageUp" || event.keyIdentifier === "PageDown");
+        if (arrowKeyOrMouseWheelEvent || pageKeyPressed) {
+            var newValue = WebInspector.createReplacementString(inputElement.value, event);
+            if (newValue) {
+                inputElement.value = newValue;
+                inputElement.selectionStart = 0;
+                inputElement.selectionEnd = newValue.length;
+            }
+        }
 
         const cf = WebInspector.Color.Format;
         var colorString;
         if (this._currentFormat === cf.HEX || this._currentFormat === cf.ShortHEX) {
             colorString = this._hexValue.value;
         } else {
             var format = this._currentFormat === cf.RGB ? "rgba" : "hsla";
             var values = this._textValues.map(elementValue).join(",");
             colorString = String.sprintf("%s(%s)", format, values);
         }
@@ skipping 50 matching lines @@
         var rgba = [rgbColor.r, rgbColor.g, rgbColor.b, (rgbColor.a / 2.55 | 0) / 100];
         var color = WebInspector.Color.fromRGBA(rgba);
         this.setColor(color);
         this._dispatchChangeEvent();
         InspectorFrontendHost.bringToFront();
     },
 
 
     __proto__: WebInspector.VBox.prototype
 }