Change hittest node to be scrollbar's parent when hittest include a scrollbar

third_party/WebKit/Source/core/layout/LayoutView.cpp

Index: third_party/WebKit/Source/core/layout/LayoutView.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutView.cpp b/third_party/WebKit/Source/core/layout/LayoutView.cpp
index 374293e898c154a038231f87d6e7e1010b63b406..12b49a4a86be2b0563b817d44bedd8e6c7f47b3d 100644
--- a/third_party/WebKit/Source/core/layout/LayoutView.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutView.cpp
@@ -155,6 +155,18 @@ bool LayoutView::hitTestNoLifecycleUpdate(HitTestResult& result) {
             frameView()->scrollbarAtFramePoint(framePoint))
       result.setScrollbar(frameScrollbar);
 
+    // If hitTestResult include scrollbar, innerNode should be the parent of the
+    // scrollbar.
+    if (result.scrollbar()) {
+      ScrollableArea* scrollableArea = result.scrollbar()->getScrollableArea();

[bokan, 2017/03/31 20:07:00]

We should probably clear the innerNode first. That way if we hit a scrollbar
whose scrollable area isn't associated with a LayoutBox we aren't hitting some
random element below too.

+      if (scrollableArea && scrollableArea->layoutBox() &&
+          scrollableArea->layoutBox()->node()) {
+        Node* node = scrollableArea->layoutBox()->node();
+        result.setInnerNode(node);
+        result.setURLElement(node->enclosingLinkEventParentOrSelf());

[mustaq, 2017/03/31 16:57:48]

Please add a comment for |HitTestResult.m_innerURLElement| to say that for
non-URL, it's the enclosing elem that triggers navigation.

+      }
+    }
+
     if (hitLayer)
       m_hitTestCache->addCachedResult(result, domTreeVersion);
   }