DevTools: do not scroll console to bottom on resize

Source/devtools/front_end/ui/ViewportControl.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 37 matching lines @@
     this.element.addEventListener("scroll", this._onScroll.bind(this), false);
     this.element.addEventListener("copy", this._onCopy.bind(this), false);
     this.element.addEventListener("dragstart", this._onDragStart.bind(this), false);
 
     this._firstVisibleIndex = 0;
     this._lastVisibleIndex = -1;
     this._renderedItems = [];
     this._anchorSelection = null;
     this._headSelection = null;
     this._stickToBottom = false;
+    this._scrolledToBottom = true;
 }
 
 /**
  * @interface
  */
 WebInspector.ViewportControl.Provider = function()
 {
 }
 
 WebInspector.ViewportControl.Provider.prototype = {
@@ skipping 58 matching lines @@
      * @return {!Element}
      */
     element: function()
     {
         return this._element;
     },
 }
 
 WebInspector.ViewportControl.prototype = {
     /**
+     * @return {boolean}
+     */
+    scrolledToBottom: function()
+    {
+        return this._scrolledToBottom;
+    },
+
+    /**
      * @param {boolean} value
      */
     setStickToBottom: function(value)
     {
         this._stickToBottom = value;
     },
 
     /**
      * @param {!Event} event
      */
@@ skipping 220 matching lines @@
             this._firstVisibleIndex = -1;
             this._lastVisibleIndex = -1;
             return;
         }
 
         var selection = window.getSelection();
         var shouldRestoreSelection = this._updateSelectionModel(selection);
 
         var visibleFrom = this.element.scrollTop;
         var visibleHeight = this._visibleHeight();
-        var shouldStickToBottom = this._stickToBottom && this.element.isScrolledToBottom();
+        this._scrolledToBottom = this.element.isScrolledToBottom();
         var isInvalidating = !this._cumulativeHeights;
 
         if (this._cumulativeHeights && itemCount !== this._cumulativeHeights.length)
             delete this._cumulativeHeights;
         for (var i = 0; i < this._renderedItems.length; ++i) {
             this._renderedItems[i].cacheFastHeight();
             // Tolerate 1-pixel error due to double-to-integer rounding errors.
             if (this._cumulativeHeights && Math.abs(this._cachedItemHeight(this._firstVisibleIndex + i) - this._provider.fastHeight(i + this._firstVisibleIndex)) > 1)
                 delete this._cumulativeHeights;
         }
         this._rebuildCumulativeHeightsIfNeeded();
         var oldFirstVisibleIndex = this._firstVisibleIndex;
         var oldLastVisibleIndex = this._lastVisibleIndex;
+
+        var shouldStickToBottom = this._stickToBottom && this._scrolledToBottom;
         if (shouldStickToBottom) {
             this._lastVisibleIndex = itemCount - 1;
             this._firstVisibleIndex = Math.max(itemCount - Math.ceil(visibleHeight / this._provider.minimumRowHeight()), 0);
         } else {
             this._firstVisibleIndex = Math.max(Array.prototype.lowerBound.call(this._cumulativeHeights, visibleFrom + 1), 0);
             // Proactively render more rows in case some of them will be collapsed without triggering refresh. @see crbug.com/390169
             this._lastVisibleIndex = this._firstVisibleIndex + Math.ceil(visibleHeight / this._provider.minimumRowHeight()) - 1;
             this._lastVisibleIndex = Math.min(this._lastVisibleIndex, itemCount - 1);
         }
         var topGapHeight = this._cumulativeHeights[this._firstVisibleIndex - 1] || 0;
@@ skipping 190 matching lines @@
 
     /**
      * @return {number}
      */
     _visibleHeight: function()
     {
         // Use offsetHeight instead of clientHeight to avoid being affected by horizontal scroll.
         return this.element.offsetHeight;
     }
 }