De-duplicate empty line handling in InlineBlockBaseline() of LayoutBlock and LayoutBlockFlow

This CL merges duplicated code into LayoutBlock::EmptyLineBaseline().
This CL has no behavior changes.

Bug: 1040828
Change-Id: Ibef264899797f5e443b2485a098d555fe93a949b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2015870Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Commit-Queue: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#734356}

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

@@ -1682,6 +1682,24 @@ bool LayoutBlock::HasLineIfEmpty() const {
   return false;
 }
 
+LayoutUnit LayoutBlock::EmptyLineBaseline(
+    LineDirectionMode line_direction) const {
+  if (!HasLineIfEmpty())
+    return LayoutUnit(-1);
+  const SimpleFontData* font_data = FirstLineStyle()->GetFont().PrimaryFont();
+  if (!font_data)
+    return LayoutUnit(-1);
+  const auto& font_metrics = font_data->GetFontMetrics();
+  const LayoutUnit line_height =
+      LineHeight(true, line_direction, kPositionOfInteriorLineBoxes);
+  const LayoutUnit border_padding = line_direction == kHorizontalLine
+                                        ? BorderTop() + PaddingTop()
+                                        : BorderRight() + PaddingRight();
+  return LayoutUnit((font_metrics.Ascent() +
+                     (line_height - font_metrics.Height()) / 2 + border_padding)
+                        .ToInt());
+}
+
 LayoutUnit LayoutBlock::LineHeight(bool first_line,
                                    LineDirectionMode direction,
                                    LinePositionMode line_position_mode) const {
@@ -1849,18 +1867,8 @@ LayoutUnit LayoutBlock::InlineBlockBaseline(
       }
     }
   }
-  const SimpleFontData* font_data = FirstLineStyle()->GetFont().PrimaryFont();
-  if (font_data && !have_normal_flow_child && HasLineIfEmpty()) {
-    const FontMetrics& font_metrics = font_data->GetFontMetrics();
-    return LayoutUnit(
-        (font_metrics.Ascent() +
-         (LineHeight(true, line_direction, kPositionOfInteriorLineBoxes) -
-          font_metrics.Height()) /
-             2 +
-         (line_direction == kHorizontalLine ? BorderTop() + PaddingTop()
-                                            : BorderRight() + PaddingRight()))
-            .ToInt());
-  }
+  if (!have_normal_flow_child)
+    return EmptyLineBaseline(line_direction);
   return LayoutUnit(-1);
 }
 

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

@@ -486,6 +486,8 @@ class CORE_EXPORT LayoutBlock : public LayoutBox {
            hit_test_action == kHitTestChildBlockBackground;
   }
 
+  LayoutUnit EmptyLineBaseline(LineDirectionMode line_direction) const;
+
  private:
   LayoutObjectChildList* VirtualChildren() final { return Children(); }
   const LayoutObjectChildList* VirtualChildren() const final {

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

@@ -2541,23 +2541,7 @@ LayoutUnit LayoutBlockFlow::InlineBlockBaseline(
     return LastLineBox()->LogicalTop() +
            font_data->GetFontMetrics().Ascent(LastRootBox()->BaselineType());
   }
-  if (!HasLineIfEmpty())
-    return LayoutUnit(-1);
-
-  const SimpleFontData* font_data = FirstLineStyle()->GetFont().PrimaryFont();
-  DCHECK(font_data);
-  if (!font_data)
-    return LayoutUnit(-1);
-
-  const FontMetrics& font_metrics = font_data->GetFontMetrics();
-  return LayoutUnit(
-      (font_metrics.Ascent() +
-       (LineHeight(true, line_direction, kPositionOfInteriorLineBoxes) -
-        font_metrics.Height()) /
-           2 +
-       (line_direction == kHorizontalLine ? BorderTop() + PaddingTop()
-                                          : BorderRight() + PaddingRight()))
-          .ToInt());
+  return EmptyLineBaseline(line_direction);
 }
 
 void LayoutBlockFlow::RemoveFloatingObjectsFromDescendants() {