DevTools: Make sure flamechart vertical scroll stays within the height of contents.

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

Index: third_party/WebKit/Source/devtools/front_end/ui_lazy/FlameChart.js
diff --git a/third_party/WebKit/Source/devtools/front_end/ui_lazy/FlameChart.js b/third_party/WebKit/Source/devtools/front_end/ui_lazy/FlameChart.js
index 1449cd2e4701396a4d993c1f982f633ec825caf8..0c4b74e267768dcf6833ff63a3be6e9f037c1837 100644
--- a/third_party/WebKit/Source/devtools/front_end/ui_lazy/FlameChart.js
+++ b/third_party/WebKit/Source/devtools/front_end/ui_lazy/FlameChart.js
@@ -1950,6 +1950,10 @@ WebInspector.FlameChart.prototype = {
     {
         this._totalHeight = this._levelToHeight(this._dataProvider.maxStackDepth());
         this._vScrollContent.style.height = this._totalHeight + "px";
+        if (this._scrollTop + this._offsetHeight > this._totalHeight) {
+            this._scrollTop = Math.max(0, this._totalHeight - this._offsetHeight);
+            this._vScrollElement.scrollTop = this._scrollTop;
+        }
     },
 
     onResize: function()