[cleanup] Rename Accumulate{InFlow,Relative}PositionOffsets.

The old code was also looking at sticky positioned offsets, but it looks
like position: sticky is generally broken with split inlines so couldn't
trigger a reliable bug.

Change-Id: I82bf9c0b5cdbfb316ca095e7acb574737c63678d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2215367
Commit-Queue: Koji Ishii <kojii@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#772129}

third_party/blink/renderer/core/layout/layout_block_flow.cc

@@ -4099,14 +4099,14 @@ bool LayoutBlockFlow::HitTestFloats(HitTestResult& result,
   return false;
 }
 
-PhysicalOffset LayoutBlockFlow::AccumulateInFlowPositionOffsets() const {
+PhysicalOffset LayoutBlockFlow::AccumulateRelativePositionOffsets() const {
   if (!IsAnonymousBlock() || !IsInFlowPositioned())
     return PhysicalOffset();
   PhysicalOffset offset;
   for (const LayoutObject* p = InlineElementContinuation();
        p && p->IsLayoutInline(); p = p->Parent()) {
     if (p->IsInFlowPositioned())
-      offset += ToLayoutInline(p)->OffsetForInFlowPosition();
+      offset += ToLayoutInline(p)->RelativePositionOffset();
   }
   return offset;
 }

third_party/blink/renderer/core/layout/layout_block_flow.h

@@ -538,7 +538,7 @@ class CORE_EXPORT LayoutBlockFlow : public LayoutBlock {
                        const PhysicalOffset& accumulated_offset,
                        HitTestAction) override;
 
-  PhysicalOffset AccumulateInFlowPositionOffsets() const override;
+  PhysicalOffset AccumulateRelativePositionOffsets() const override;
 
  private:
   void ResetLayout();

third_party/blink/renderer/core/layout/layout_box_model_object.cc

@@ -742,7 +742,7 @@ bool LayoutBoxModelObject::HasAutoHeightOrContainingBlockWithAutoHeight(
 
 PhysicalOffset LayoutBoxModelObject::RelativePositionOffset() const {
   DCHECK(IsRelPositioned());
-  PhysicalOffset offset = AccumulateInFlowPositionOffsets();
+  PhysicalOffset offset = AccumulateRelativePositionOffsets();
 
   LayoutBlock* containing_block = ContainingBlock();
 

third_party/blink/renderer/core/layout/layout_box_model_object.h

@@ -473,7 +473,7 @@ class CORE_EXPORT LayoutBoxModelObject : public LayoutObject {
   // See continuation above for more details.
   void SetContinuation(LayoutBoxModelObject*);
 
-  virtual PhysicalOffset AccumulateInFlowPositionOffsets() const {
+  virtual PhysicalOffset AccumulateRelativePositionOffsets() const {
     return PhysicalOffset();
   }