[LayoutNG] Implement visual overflow for NGPhysicalTextFragment

This patch implements all the rest of logic to compute visual
overflow for NGPhysicalTextFragment.

In doing so, this patch also refactors text-emphasis logic to
share with the pre-NG code.

Bug: 636993, 714962
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_layout_ng
Change-Id: Ib800a9b4264dfe724d59fdb220e7c0d43513685a
Reviewed-on: https://chromium-review.googlesource.com/776638Reviewed-by: Emil A Eklund <eae@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#523386}

third_party/WebKit/Source/core/layout/line/InlineFlowBox.cpp

@@ -98,49 +98,28 @@ inline bool InlineFlowBox::HasEmphasisMarkBefore(
       text_box->GetLineLayoutItem().StyleRef(IsFirstLineStyle());
   if (!text_box->GetEmphasisMarkPosition(style, emphasis_mark_position))
     return false;
-  if (IsHorizontal()) {
-    return emphasis_mark_position == TextEmphasisPosition::kOverRight ||
-           emphasis_mark_position == TextEmphasisPosition::kOverLeft;
-  }
-  if (style.IsFlippedLinesWritingMode()) {
-    return emphasis_mark_position == TextEmphasisPosition::kOverLeft ||
-           emphasis_mark_position == TextEmphasisPosition::kUnderLeft;
-  }
-  if (style.IsFlippedBlocksWritingMode()) {
-    return emphasis_mark_position == TextEmphasisPosition::kOverRight ||
-           emphasis_mark_position == TextEmphasisPosition::kUnderRight;
-  }
-  return false;
+  LineLogicalSide side = style.GetTextEmphasisLineLogicalSide();
+  if (IsHorizontal() || !style.IsFlippedLinesWritingMode())
+    return side == LineLogicalSide::kOver;
+  return side == LineLogicalSide::kUnder;
 }
 
 inline bool InlineFlowBox::HasEmphasisMarkOver(
     const InlineTextBox* text_box) const {
+  const auto& style =
+      text_box->GetLineLayoutItem().StyleRef(IsFirstLineStyle());
   TextEmphasisPosition emphasis_mark_position;
-  if (!text_box->GetEmphasisMarkPosition(
-          text_box->GetLineLayoutItem().StyleRef(IsFirstLineStyle()),
-          emphasis_mark_position))
-    return false;
-
-  return IsHorizontal()
-             ? emphasis_mark_position == TextEmphasisPosition::kOverRight ||
-                   emphasis_mark_position == TextEmphasisPosition::kOverLeft
-             : emphasis_mark_position == TextEmphasisPosition::kOverRight ||
-                   emphasis_mark_position == TextEmphasisPosition::kUnderRight;
+  return text_box->GetEmphasisMarkPosition(style, emphasis_mark_position) &&
+         style.GetTextEmphasisLineLogicalSide() == LineLogicalSide::kOver;
 }
 
 inline bool InlineFlowBox::HasEmphasisMarkUnder(
     const InlineTextBox* text_box) const {
+  const auto& style =
+      text_box->GetLineLayoutItem().StyleRef(IsFirstLineStyle());
   TextEmphasisPosition emphasis_mark_position;
-  if (!text_box->GetEmphasisMarkPosition(
-          text_box->GetLineLayoutItem().StyleRef(IsFirstLineStyle()),
-          emphasis_mark_position))
-    return false;
-
-  return IsHorizontal()
-             ? emphasis_mark_position == TextEmphasisPosition::kUnderRight ||
-                   emphasis_mark_position == TextEmphasisPosition::kUnderLeft
-             : emphasis_mark_position == TextEmphasisPosition::kOverLeft ||
-                   emphasis_mark_position == TextEmphasisPosition::kUnderLeft;
+  return text_box->GetEmphasisMarkPosition(style, emphasis_mark_position) &&
+         style.GetTextEmphasisLineLogicalSide() == LineLogicalSide::kUnder;
 }
 
 void InlineFlowBox::AddToLine(InlineBox* child) {

third_party/WebKit/Source/core/layout/line/InlineTextBox.cpp

@@ -518,12 +518,7 @@ bool InlineTextBox::GetEmphasisMarkPosition(
 
   emphasis_position = style.GetTextEmphasisPosition();
   // Ruby text is always over, so it cannot suppress emphasis marks under.
-  if ((IsHorizontal() &&
-       (emphasis_position == TextEmphasisPosition::kUnderRight ||
-        emphasis_position == TextEmphasisPosition::kUnderLeft)) ||
-      (!IsHorizontal() &&
-       (emphasis_position == TextEmphasisPosition::kOverLeft ||
-        emphasis_position == TextEmphasisPosition::kUnderLeft)))
+  if (style.GetTextEmphasisLineLogicalSide() != LineLogicalSide::kOver)
     return true;
 
   LineLayoutBox containing_block = GetLineLayoutItem().ContainingBlock();

third_party/WebKit/Source/core/layout/ng/inline/ng_physical_text_fragment.cc

@@ -14,36 +14,47 @@ NGPhysicalOffsetRect NGPhysicalTextFragment::SelfVisualRect() const {
   if (!shape_result_)
     return {};
 
-  // TODO(kojii): Copying InlineTextBox logic from
-  // InlineFlowBox::ComputeOverflow().
-  //
-  // InlineFlowBox::ComputeOverflow() computes GlpyhOverflow first
-  // (ComputeGlyphOverflow) then AddTextBoxVisualOverflow(). We probably don't
-  // have to keep these two steps separated.
-
-  // Glyph bounds is in logical coordinate, origin at the baseline.
-  FloatRect visual_float_rect = shape_result_->Bounds();
+  // Glyph bounds is in logical coordinate, origin at the alphabetic baseline.
+  LayoutRect visual_rect = EnclosingLayoutRect(shape_result_->Bounds());
 
   // Make the origin at the logical top of this fragment.
-  // ShapeResult::Bounds() is in logical coordinate with alphabetic baseline.
   const ComputedStyle& style = Style();
-  const SimpleFontData* font_data = style.GetFont().PrimaryFont();
-  visual_float_rect.SetY(
-      visual_float_rect.Y() +
-      font_data->GetFontMetrics().FixedAscent(kAlphabeticBaseline));
+  const Font& font = style.GetFont();
+  const SimpleFontData* font_data = font.PrimaryFont();
+  if (font_data) {
+    visual_rect.SetY(visual_rect.Y() + font_data->GetFontMetrics().FixedAscent(
+                                           kAlphabeticBaseline));
+  }
 
-  // TODO(kojii): Copying from AddTextBoxVisualOverflow()
   if (float stroke_width = style.TextStrokeWidth()) {
-    visual_float_rect.Inflate(stroke_width / 2.0f);
+    visual_rect.Inflate(LayoutUnit::FromFloatCeil(stroke_width / 2.0f));
   }
 
-  // TODO(kojii): Implement emphasis marks.
+  if (style.GetTextEmphasisMark() != TextEmphasisMark::kNone) {
+    LayoutUnit emphasis_mark_height =
+        LayoutUnit(font.EmphasisMarkHeight(style.TextEmphasisMarkString()));
+    DCHECK_GT(emphasis_mark_height, LayoutUnit());
+    if (style.GetTextEmphasisLineLogicalSide() == LineLogicalSide::kOver) {
+      visual_rect.ShiftYEdgeTo(
+          std::min(visual_rect.Y(), -emphasis_mark_height));
+    } else {
+      LayoutUnit logical_height =
+          style.IsHorizontalWritingMode() ? Size().height : Size().width;
+      visual_rect.ShiftMaxYEdgeTo(
+          std::max(visual_rect.MaxY(), logical_height + emphasis_mark_height));
+    }
+  }
 
   if (ShadowList* text_shadow = style.TextShadow()) {
-    // TODO(kojii): Implement text shadow.
+    LayoutRectOutsets text_shadow_logical_outsets =
+        LayoutRectOutsets(text_shadow->RectOutsetsIncludingOriginal())
+            .LineOrientationOutsets(style.GetWritingMode());
+    text_shadow_logical_outsets.ClampNegativeToZero();
+    visual_rect.Expand(text_shadow_logical_outsets);
   }
 
-  LayoutRect visual_rect = EnclosingLayoutRect(visual_float_rect);
+  visual_rect = LayoutRect(EnclosingIntRect(visual_rect));
+
   switch (LineOrientation()) {
     case NGLineOrientation::kHorizontal:
       return NGPhysicalOffsetRect(visual_rect);

third_party/WebKit/Source/core/style/ComputedStyle.cpp

@@ -1359,6 +1359,26 @@ const AtomicString& ComputedStyle::TextEmphasisMarkString() const {
   return g_null_atom;
 }
 
+LineLogicalSide ComputedStyle::GetTextEmphasisLineLogicalSide() const {
+  TextEmphasisPosition position = GetTextEmphasisPosition();
+  if (IsHorizontalWritingMode()) {
+    return position == TextEmphasisPosition::kOverRight ||
+                   position == TextEmphasisPosition::kOverLeft
+               ? LineLogicalSide::kOver
+               : LineLogicalSide::kUnder;
+  }
+  if (GetWritingMode() != WritingMode::kSidewaysLr) {
+    return position == TextEmphasisPosition::kOverRight ||
+                   position == TextEmphasisPosition::kUnderRight
+               ? LineLogicalSide::kOver
+               : LineLogicalSide::kUnder;
+  }
+  return position == TextEmphasisPosition::kOverLeft ||
+                 position == TextEmphasisPosition::kUnderLeft
+             ? LineLogicalSide::kOver
+             : LineLogicalSide::kUnder;
+}
+
 CSSAnimationData& ComputedStyle::AccessAnimations() {
   if (!AnimationsInternal())
     SetAnimationsInternal(CSSAnimationData::Create());

third_party/WebKit/Source/core/style/ComputedStyle.h

@@ -878,6 +878,7 @@ class ComputedStyle : public ComputedStyleBase,
     SetTextEmphasisMarkInternal(mark);
   }
   const AtomicString& TextEmphasisMarkString() const;
+  LineLogicalSide GetTextEmphasisLineLogicalSide() const;
 
   // -webkit-text-emphasis-color (aka -epub-text-emphasis-color)
   void SetTextEmphasisColor(const StyleColor& color) {

third_party/WebKit/Source/core/style/ComputedStyleConstants.h

@@ -248,6 +248,11 @@ enum TextEmphasisPosition {
   kUnderLeft,
 };
 
+enum class LineLogicalSide {
+  kOver,
+  kUnder,
+};
+
 }  // namespace blink
 
 #endif  // ComputedStyleConstants_h