Get rid of unused function NGPaintFragment::GetForInlineContainer()

This patch gets rid of unused function |GetForInlineContainer()| in
|NGPaintFragment| for improving code health.

Note: The CL[1] gets rid of the last caller of this.

[1] http://crrev.com/c/1877505 Utilize NGInlineCursor
ComputeNGLocal{Caret,Selection}Rect()

Change-Id: I0f191f711a4d55b5a67e92068a7cb4522dcb19f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1881001
Commit-Queue: Yoshifumi Inoue <yosin@chromium.org>
Auto-Submit: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#710239}

third_party/blink/renderer/core/paint/ng/ng_paint_fragment.cc

@@ -605,24 +605,6 @@ void NGPaintFragment::ClearAssociationWithLayoutObject() {
   }
 }
 
-const NGPaintFragment* NGPaintFragment::GetForInlineContainer(
-    const LayoutObject* layout_object) {
-  DCHECK(layout_object && layout_object->IsInline());
-  if (LayoutBlockFlow* block_flow = layout_object->ContainingNGBlockFlow()) {
-    if (const NGPaintFragment* fragment = block_flow->PaintFragment())
-      return fragment;
-
-    // TODO(kojii): IsLayoutFlowThread should probably be done in
-    // ContainingNGBlockFlow(), but there seem to be both expectations today.
-    // This needs cleanup.
-    if (block_flow->IsLayoutFlowThread()) {
-      DCHECK(block_flow->Parent() && block_flow->Parent()->IsLayoutBlockFlow());
-      return block_flow->Parent()->PaintFragment();
-    }
-  }
-  return nullptr;
-}
-
 NGPaintFragment::FragmentRange NGPaintFragment::InlineFragmentsFor(
     const LayoutObject* layout_object) {
   DCHECK(layout_object);

third_party/blink/renderer/core/paint/ng/ng_paint_fragment.h

@@ -252,14 +252,6 @@ class CORE_EXPORT NGPaintFragment : public RefCounted<NGPaintFragment>,
     bool is_in_layout_ng_inline_formatting_context_;
   };
 
-  // Returns NGPaintFragment for the inline formatting context the LayoutObject
-  // belongs to.
-  //
-  // When the LayoutObject is an inline block, it belongs to an inline
-  // formatting context while it creates its own for its descendants. This
-  // function always returns the one it belongs to.
-  static const NGPaintFragment* GetForInlineContainer(const LayoutObject*);
-
   // Returns a range of NGPaintFragment in an inline formatting context that are
   // for a LayoutObject.
   static FragmentRange InlineFragmentsFor(const LayoutObject*);