[RLS] Implement GetTickmarks for RootLayerScrolling

Currently GetTickmarks is not implemented in PLSA so the tickmarks are
not getting painted for RLS flow.
Implemented this function now and updated testExpectations.

BUG=711474

Change-Id: I150dfd413d2ae015e7e9e2dad94d1116df049fb3
Reviewed-on: https://chromium-review.googlesource.com/578831Reviewed-by: Steve Kobes <skobes@chromium.org>
Commit-Queue: srirama chandra sekhar <srirama.m@samsung.com>
Cr-Commit-Position: refs/heads/master@{#490724}

third_party/WebKit/LayoutTests/TestExpectations

@@ -1198,9 +1198,6 @@ crbug.com/504706 [ Linux ] inspector/profiler/heap-snapshot-containment-sorting.
 # By about a quarter or less of a pixel.
 crbug.com/421412 [ Mac ] fast/text/international/bdo-bidi-width.html [ Failure ]
 
-crbug.com/417782 virtual/rootlayerscrolls/fast/scrolling/scrollbar-tickmarks-styled.html [ Failure ]
-crbug.com/417782 virtual/rootlayerscrolls/fast/scrolling/scrollbar-tickmarks-styled-after-onload.html [ Failure ]
-
 crbug.com/574283 [ Mac ] fast/scroll-behavior/smooth-scroll/ongoing-smooth-scroll-anchors.html [ Skip ]
 crbug.com/574283 [ Mac ] virtual/scroll_customization/fast/scroll-behavior/smooth-scroll/ongoing-smooth-scroll-anchors.html [ Skip ]
 crbug.com/574283 [ Mac ] virtual/threaded/fast/scroll-behavior/first-scroll-runs-on-compositor.html [ Skip ]

third_party/WebKit/Source/core/frame/LocalFrameView.cpp

@@ -2662,7 +2662,9 @@ bool LocalFrameView::IsActive() const {
 }
 
 void LocalFrameView::InvalidatePaintForTickmarks() {
-  if (Scrollbar* scrollbar = VerticalScrollbar()) {
+  ScrollableArea* scrollable_area = LayoutViewportScrollableArea();
+  DCHECK(scrollable_area);
+  if (Scrollbar* scrollbar = scrollable_area->VerticalScrollbar()) {
     scrollbar->SetNeedsPaintInvalidation(
         static_cast<ScrollbarPart>(~kThumbPart));
   }

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp

@@ -51,6 +51,7 @@
 #include "core/dom/ShadowRoot.h"
 #include "core/dom/TaskRunnerHelper.h"
 #include "core/editing/FrameSelection.h"
+#include "core/editing/markers/DocumentMarkerController.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/LocalFrameClient.h"
 #include "core/frame/LocalFrameView.h"
@@ -2059,6 +2060,11 @@ PaintLayerScrollableArea::GetCompositorAnimationTimeline() const {
       ->GetCompositorAnimationTimeline();
 }
 
+void PaintLayerScrollableArea::GetTickmarks(Vector<IntRect>& tickmarks) const {
+  if (layer_.IsRootLayer())
+    tickmarks = Box().GetDocument().Markers().LayoutRectsForTextMatchMarkers();
+}
+
 PaintLayerScrollableArea*
 PaintLayerScrollableArea::ScrollbarManager::ScrollableArea() {
   return ToPaintLayerScrollableArea(scrollable_area_.Get());

third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.h

@@ -294,6 +294,7 @@ class CORE_EXPORT PaintLayerScrollableArea final
   ScrollBehavior ScrollBehaviorStyle() const override;
   CompositorAnimationHost* GetCompositorAnimationHost() const override;
   CompositorAnimationTimeline* GetCompositorAnimationTimeline() const override;
+  void GetTickmarks(Vector<IntRect>&) const override;
 
   // These are temporary convenience methods.  They delegate to Box() methods,
   // which will be up-to-date when UpdateAfterLayout runs.  By contrast,