DevTools: [Responsive design] shift-drag resize widget for more precise dragging

Source/devtools/front_end/ResponsiveDesignView.js

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 /**
  * @constructor
  * @extends {WebInspector.VBox}
  * @implements {WebInspector.OverridesSupport.PageResizer}
  * @param {!WebInspector.InspectedPagePlaceholder} inspectedPagePlaceholder
  */
@@ skipping 148 matching lines @@
         resizer.addEventListener(WebInspector.ResizerWidget.Events.ResizeEnd, this._onResizeEnd, this);
         return resizer;
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _onResizeStart: function(event)
     {
         var available = this.availableDipSize();
+        this._slowPositionStart = null;
         this._resizeStartSize = event.target.isVertical() ? (this._dipHeight || available.height) : (this._dipWidth || available.width);
     },
 
     /**
      * @param {!WebInspector.Event} event
      */
     _onResizeUpdate: function(event)
     {
-        var cssOffset = event.data.currentPosition - event.data.startPosition;
-        var dipOffset = cssOffset * WebInspector.zoomManager.zoomFactor();
+        if (event.data.shiftKey !== !!this._slowPositionStart)
+            this._slowPositionStart = event.data.shiftKey ? event.data.currentPosition : null;
+        var cssOffset = this._slowPositionStart ? (event.data.currentPosition - this._slowPositionStart) / 10 + this._slowPositionStart - event.data.startPosition : event.data.currentPosition - event.data.startPosition;
+        var dipOffset = Math.round(cssOffset * WebInspector.zoomManager.zoomFactor());

[lushnikov, 2014/06/04 09:15:42]

added Math.round statement we've talked about.

         var newSize = Math.max(this._resizeStartSize + dipOffset, 1);
         var requested = new Size(this._dipWidth, this._dipHeight);
         if (event.target.isVertical())
             requested.height = newSize;
         else
             requested.width = newSize;
         this.dispatchEventToListeners(WebInspector.OverridesSupport.PageResizer.Events.ResizeRequested, requested);
     },
 
     /**
@@ skipping 272 matching lines @@
         if (this._warningMessage.textContent === message)
             return;
         this._warningMessage.classList.toggle("hidden", !message);
         this._warningMessage.textContent = message;
         this._responsiveDesignModeChanged();
         this.onResize();
     },
 
     __proto__: WebInspector.VBox.prototype
 };