Cleanup unused member of GranularityStrategyTest

Member function SetSelectionAndEndTyping()
was never used, instead FrameSelection
SetSelectionAndEndTyping was used directly.
So this is removed as a DeadCode

Bug: 867563
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng
Change-Id: I7d45dd28597e66cfb4ce35db28474136b5283356
Reviewed-on: https://chromium-review.googlesource.com/1158109
Commit-Queue: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#579741}

third_party/blink/renderer/core/editing/granularity_strategy_test.cc

@@ -41,7 +41,6 @@ class GranularityStrategyTest : public PageTestBase {
  protected:
   void SetUp() override;
 
-  void SetSelectionAndEndTyping(const VisibleSelection&);
   Text* AppendTextNode(const String& data);
   int LayoutCount() const {
     return GetDummyPageHolder().GetFrameView().LayoutCount();
@@ -88,11 +87,6 @@ void GranularityStrategyTest::SetUp() {
   GetFrame().GetSettings()->SetSelectionStrategy(SelectionStrategy::kDirection);
 }
 
-void GranularityStrategyTest::SetSelectionAndEndTyping(
-    const VisibleSelection& new_selection) {
-  Selection().SetSelectionAndEndTyping(new_selection.AsSelection());
-}
-
 Text* GranularityStrategyTest::AppendTextNode(const String& data) {
   Text* text = GetDocument().createTextNode(data);
   GetDocument().body()->AppendChild(text);