Bug 1328065 - Better document scrollbar-related fields in HitTestingTreeNode. r=kats
authorBotond Ballo <botond@mozilla.com>
Fri, 17 Feb 2017 15:42:30 -0500
changeset 373356 a6eebf52669f7893a1e640425617ea18b76e024d
parent 373355 3ff84674e9e08029b91b005834ee70bab176a07d
child 373357 b27f0473cd580aac5c996ea0de6e0e62f164edb0
push id10863
push userjlorenzo@mozilla.com
push dateMon, 06 Mar 2017 23:02:23 +0000
treeherdermozilla-aurora@0931190cd725 [default view] [failures only]
perfherder[talos] [build metrics] [platform microbench] (compared to previous push)
reviewerskats
bugs1328065
milestone54.0a1
Bug 1328065 - Better document scrollbar-related fields in HitTestingTreeNode. r=kats MozReview-Commit-ID: 3q3Kgs33qP0
gfx/layers/apz/src/HitTestingTreeNode.h
--- a/gfx/layers/apz/src/HitTestingTreeNode.h
+++ b/gfx/layers/apz/src/HitTestingTreeNode.h
@@ -123,19 +123,25 @@ private:
   RefPtr<HitTestingTreeNode> mPrevSibling;
   RefPtr<HitTestingTreeNode> mParent;
 
   RefPtr<AsyncPanZoomController> mApzc;
   bool mIsPrimaryApzcHolder;
 
   uint64_t mLayersId;
 
+  // This is set for both scroll track and scroll thumb Container layers, and
+  // represents the scroll id of the scroll frame scrolled by the scrollbar.
   FrameMetrics::ViewID mScrollViewId;
+
+  // This is set for scroll thumb Container layers only.
   ScrollDirection mScrollDir;
   int32_t mScrollThumbLength;
+
+  // This is set for scroll track Container layers only.
   bool mIsScrollbarContainer;
 
   FrameMetrics::ViewID mFixedPosTarget;
 
   /* Let {L,M} be the {layer, scrollable metrics} pair that this node
    * corresponds to in the layer tree. mEventRegions contains the event regions
    * from L, in the case where event-regions are enabled. If event-regions are
    * disabled, it will contain the visible region of L, which we use as an