DevTools: Fix scrolling of timeline flamechart

third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js

Index: third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js
diff --git a/third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js b/third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js
index 2d8ad8a6d591daaf261b96889c47b36d33e1f31b..270ce48458f42e2a99c951edd6f85720119877ee 100644
--- a/third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js
+++ b/third_party/WebKit/Source/devtools/front_end/ui_lazy/ChartViewport.js
@@ -13,8 +13,10 @@ WebInspector.ChartViewport = function()
     this.contentElement.addEventListener("mousewheel", this._onMouseWheel.bind(this), false);
     this.contentElement.addEventListener("keydown", this._handleZoomPanKeys.bind(this), false);
 
-    WebInspector.installInertialDragHandle(this.contentElement, this._startDragging.bind(this), this._dragging.bind(this), this._endDragging.bind(this), "-webkit-grabbing", null);
-    WebInspector.installDragHandle(this.contentElement, this._startRangeSelection.bind(this), this._rangeSelectionDragging.bind(this), this._endRangeSelection.bind(this), "text", null);
+    /** @private */

[caseq, 2016/10/20 21:33:51]

let's not use it on all privates. perhaps rather fix the compiler?

[alph, 2016/10/20 22:59:37]

Done.

+    this._dragContainer = this.contentElement.createChild("div", "fill");

[caseq, 2016/10/20 21:33:51]

I don't think this is good approach.

[alph, 2016/10/20 22:59:38]

I'd really appreciate if you can suggest anything better. 

+    WebInspector.installInertialDragHandle(this._dragContainer, this._startDragging.bind(this), this._dragging.bind(this), this._endDragging.bind(this), "-webkit-grabbing", null);
+    WebInspector.installDragHandle(this._dragContainer, this._startRangeSelection.bind(this), this._rangeSelectionDragging.bind(this), this._endRangeSelection.bind(this), "text", null);
 
     /** @private */
     this._vScrollElement = this.contentElement.createChild("div", "flame-chart-v-scroll");
@@ -53,10 +55,10 @@ WebInspector.ChartViewport.prototype = {
     _updateScrollBar: function()
     {
         var showScroll = this._totalHeight > this._offsetHeight;
-        if (this._vScrollElement.classList.contains("hidden") === showScroll) {
-            this._vScrollElement.classList.toggle("hidden", !showScroll);
-            this._updateContentElementSize();
-        }
+        if (this._vScrollElement.classList.contains("hidden") !== showScroll)
+            return;
+        this._vScrollElement.classList.toggle("hidden", !showScroll);
+        this._updateContentElementSize();
     },
 
     /**
@@ -79,8 +81,6 @@ WebInspector.ChartViewport.prototype = {
         /** @private */
         this._rangeSelectionEnd = 0;
         /** @private */
-        this._scrollTop = 0;
-        /** @private */
         this._isDragging = false;
         /** @private */
         this._dragStartPointX = 0;