Cleanup |fragment| usages in |PaintObject|

This patch unifies two different access to |box_fragment_|,
one as a field and one as a local variable, in |PaintObject|.

This patch has no behavior changes.

Change-Id: I2075fc9c88e62fafe0575c84a6a1310c2c3f5531
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2557701
Auto-Submit: Koji Ishii <kojii@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#830869}

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

@@ -538,9 +538,9 @@ void NGBoxFragmentPainter::PaintObject(
     const PhysicalOffset& paint_offset,
     bool suppress_box_decoration_background) {
   const PaintPhase paint_phase = paint_info.phase;
-  const NGPhysicalBoxFragment& physical_box_fragment = PhysicalFragment();
-  const ComputedStyle& style = box_fragment_.Style();
-  bool is_visible = IsVisibleToPaint(physical_box_fragment, style);
+  const NGPhysicalBoxFragment& fragment = PhysicalFragment();
+  const ComputedStyle& style = fragment.Style();
+  bool is_visible = IsVisibleToPaint(fragment, style);
   if (ShouldPaintSelfBlockBackground(paint_phase)) {
     if (is_visible) {
       PaintBoxDecorationBackground(paint_info, paint_offset,
@@ -558,21 +558,20 @@ void NGBoxFragmentPainter::PaintObject(
 
   if (paint_phase == PaintPhase::kForeground) {
     if (paint_info.ShouldAddUrlMetadata()) {
-      NGFragmentPainter(box_fragment_, GetDisplayItemClient())
+      NGFragmentPainter(fragment, GetDisplayItemClient())
           .AddURLRectIfNeeded(paint_info, paint_offset);
     }
-    if (is_visible && box_fragment_.HasExtraMathMLPainting())
-      NGMathMLPainter(box_fragment_).Paint(paint_info, paint_offset);
+    if (is_visible && fragment.HasExtraMathMLPainting())
+      NGMathMLPainter(fragment).Paint(paint_info, paint_offset);
   }
 
   // Paint children.
   if (paint_phase != PaintPhase::kSelfOutlineOnly &&
-      (!physical_box_fragment.Children().empty() ||
-       physical_box_fragment.HasItems() || inline_box_cursor_) &&
+      (!fragment.Children().empty() || fragment.HasItems() ||
+       inline_box_cursor_) &&
       !paint_info.DescendantPaintingBlocked()) {
     if (is_visible && UNLIKELY(paint_phase == PaintPhase::kForeground &&
-                               box_fragment_.IsCSSBox() &&
-                               box_fragment_.Style().HasColumnRule()))
+                               fragment.IsCSSBox() && style.HasColumnRule()))
       PaintColumnRules(paint_info, paint_offset);
 
     if (paint_phase != PaintPhase::kFloat) {
@@ -589,15 +588,15 @@ void NGBoxFragmentPainter::PaintObject(
                          paint_offset_to_inline_formatting_context,
                          box_item_->OffsetInContainerBlock(), &descendants);
       } else if (items_) {
-        if (physical_box_fragment.IsBlockFlow()) {
+        if (fragment.IsBlockFlow()) {
           PaintBlockFlowContents(paint_info, paint_offset);
         } else {
-          DCHECK(physical_box_fragment.IsInlineBox());
-          NGInlineCursor cursor(physical_box_fragment, *items_);
+          DCHECK(fragment.IsInlineBox());
+          NGInlineCursor cursor(fragment, *items_);
           PaintInlineItems(paint_info.ForDescendants(), paint_offset,
                            PhysicalOffset(), &cursor);
         }
-      } else if (!physical_box_fragment.IsInlineFormattingContext()) {
+      } else if (!fragment.IsInlineFormattingContext()) {
         PaintBlockChildren(paint_info, paint_offset);
       } else if (!RuntimeEnabledFeatures::LayoutNGFragmentItemEnabled()) {
         // This is the NGPaintFragment code path. We need the check for
@@ -624,7 +623,7 @@ void NGBoxFragmentPainter::PaintObject(
         // the remaining 50px of #fl - no items (all in-flow content fits in the
         // first fragment).
         DCHECK(paint_fragment_);
-        if (physical_box_fragment.IsBlockFlow()) {
+        if (fragment.IsBlockFlow()) {
           PaintBlockFlowContents(paint_info, paint_offset);
         } else if (ShouldPaintDescendantOutlines(paint_info.phase)) {
           // TODO(kojii): |PaintInlineChildrenOutlines()| should do the work
@@ -642,13 +641,13 @@ void NGBoxFragmentPainter::PaintObject(
     if (paint_phase == PaintPhase::kFloat ||
         paint_phase == PaintPhase::kSelectionDragImage ||
         paint_phase == PaintPhase::kTextClip) {
-      if (physical_box_fragment.HasFloatingDescendantsForPaint())
+      if (fragment.HasFloatingDescendantsForPaint())
         PaintFloats(paint_info);
     }
   }
 
   if (is_visible && ShouldPaintSelfOutline(paint_phase)) {
-    NGFragmentPainter(box_fragment_, GetDisplayItemClient())
+    NGFragmentPainter(fragment, GetDisplayItemClient())
         .PaintOutline(paint_info, paint_offset);
   }
 }