[LayoutNG] Implement line-box avoidance of floats correctly.

This asks for the layout opporunties up front, then iterates through them
attempting to construct a line for each one, until something fits.

There are two checks:
1) For the inline-size of a linebox, directly after the line breaker has run.
2) For the block-size, after we've determined the line-height.

Bug: 	635619
Change-Id: Icb88791be2c4d267b1361c4a7ed47dec71b9a87d
Reviewed-on: https://chromium-review.googlesource.com/742041
Commit-Queue: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#513318}

third_party/WebKit/LayoutTests/TestExpectations

@@ -308,12 +308,6 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-bfc-
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-bfc-003-right-overflow.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-bfc-004.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-bfc-006.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-top-below-inline-001l.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-top-below-inline-001r.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-top-below-inline-002l.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-top-below-inline-002r.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-top-below-inline-003l.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-wrap-top-below-inline-003r.xht [ Failure ]
 crbug.com/723135 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-zero-height-wrap-001.xht [ Failure ]
 crbug.com/723135 virtual/layout_ng/external/wpt/css/CSS2/floats/floats-zero-height-wrap-002.xht [ Failure ]
 
@@ -500,17 +494,9 @@ crbug.com/635619 virtual/layout_ng/fast/block/float/float-reparent-during-detach
 crbug.com/635619 virtual/layout_ng/fast/block/float/floats-and-text-indent-rl.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/floats-and-text-indent.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/floats-do-not-overhang-from-block-formatting-context.html [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-offset-image-quirk-line-height.html [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-offset-image-quirk.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/floats-offset-image-strict-line-height.html [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-offset-image-strict.html [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-offset-inline-block-quirk-line-height.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/floats-offset-inline-block-strict-line-height.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/floats-with-margin-should-not-wrap.html [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-wrap-inside-inline-001.htm [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-wrap-inside-inline-002.htm [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-wrap-inside-inline-003.htm [ Failure ]
-crbug.com/635619 virtual/layout_ng/fast/block/float/floats-wrap-inside-inline-004.htm [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/independent-align-positioning.html [ Failure ]
 crbug.com/635619 [ Mac ] virtual/layout_ng/fast/block/float/intruding-painted-twice.html [ Failure ]
 crbug.com/635619 virtual/layout_ng/fast/block/float/line-break-after-white-space-crash.html [ Pass Crash Timeout ]

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

@@ -17,6 +17,33 @@ const char* kNGInlineItemTypeStrings[] = {
     "Text",     "Control",  "AtomicInline",        "OpenTag",
     "CloseTag", "Floating", "OutOfFlowPositioned", "BidiControl"};
 
+// Returns true if this item is "empty", i.e. if the node contains only empty
+// items it will produce a single zero block-size line box.
+static bool IsEmptyItem(NGInlineItem::NGInlineItemType type,
+                        const ComputedStyle* style) {
+  if (type == NGInlineItem::kAtomicInline || type == NGInlineItem::kControl ||
+      type == NGInlineItem::kText)
+    return false;
+
+  if (type == NGInlineItem::kOpenTag) {
+    DCHECK(style);
+
+    if (!style->MarginStart().IsZero() || style->BorderStart().NonZero() ||
+        !style->PaddingStart().IsZero())
+      return false;
+  }
+
+  if (type == NGInlineItem::kCloseTag) {
+    DCHECK(style);
+
+    if (!style->MarginEnd().IsZero() || style->BorderEnd().NonZero() ||
+        !style->PaddingEnd().IsZero())
+      return false;
+  }
+
+  return true;
+}
+
 }  // namespace
 
 NGInlineItem::NGInlineItem(NGInlineItemType type,
@@ -31,7 +58,8 @@ NGInlineItem::NGInlineItem(NGInlineItemType type,
       layout_object_(layout_object),
       type_(type),
       bidi_level_(UBIDI_LTR),
-      shape_options_(kPreContext | kPostContext) {
+      shape_options_(kPreContext | kPostContext),
+      is_empty_item_(::blink::IsEmptyItem(type, style)) {
   DCHECK_GE(end, start);
 }
 

third_party/WebKit/Source/core/layout/ng/inline/ng_inline_item.h

@@ -65,6 +65,9 @@ class CORE_EXPORT NGInlineItem {
     return static_cast<NGLayoutInlineShapeOptions>(shape_options_);
   }
 
+  // If this item is "empty" for the purpose of empty block calculation.
+  bool IsEmptyItem() const { return is_empty_item_; }
+
   unsigned StartOffset() const { return start_offset_; }
   unsigned EndOffset() const { return end_offset_; }
   unsigned Length() const { return end_offset_ - start_offset_; }
@@ -111,6 +114,7 @@ class CORE_EXPORT NGInlineItem {
   unsigned type_ : 4;
   unsigned bidi_level_ : 8;  // UBiDiLevel is defined as uint8_t.
   unsigned shape_options_ : 2;
+  unsigned is_empty_item_ : 1;
 
   friend class NGInlineNode;
 };

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

@@ -48,9 +48,11 @@ void NGLineInfo::SetLineStyle(const NGInlineNode& node,
 }
 
 void NGLineInfo::SetLineBfcOffset(NGBfcOffset line_bfc_offset,
-                                  LayoutUnit available_width) {
+                                  LayoutUnit available_width,
+                                  LayoutUnit width) {
   line_bfc_offset_ = line_bfc_offset;
   available_width_ = available_width;
+  width_ = width;
 }
 
 void NGLineInfo::SetLineEndShapeResult(

third_party/WebKit/Source/core/layout/ng/inline/ng_inline_item_result.h

@@ -131,8 +131,10 @@ class CORE_EXPORT NGLineInfo {
 
   NGBfcOffset LineBfcOffset() const { return line_bfc_offset_; }
   LayoutUnit AvailableWidth() const { return available_width_; }
+  LayoutUnit Width() const { return width_; }
   void SetLineBfcOffset(NGBfcOffset line_bfc_offset,
-                        LayoutUnit available_width);
+                        LayoutUnit available_width,
+                        LayoutUnit width);
 
   // Start/end text offset of this line.
   unsigned StartOffset() const { return start_offset_; }
@@ -162,6 +164,7 @@ class CORE_EXPORT NGLineInfo {
 
   NGBfcOffset line_bfc_offset_;
   LayoutUnit available_width_;
+  LayoutUnit width_;
   LayoutUnit text_indent_;
 
   unsigned start_offset_;

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

@@ -106,33 +106,6 @@ static bool ShouldRemoveNewline(const StringBuilder& before,
                                  after_style);
 }
 
-// Returns true if this item is "empty", i.e. if the node contains only empty
-// items it will produce a single zero block-size line box.
-static bool IsItemEmpty(NGInlineItem::NGInlineItemType type,
-                        const ComputedStyle* style) {
-  if (type == NGInlineItem::kAtomicInline || type == NGInlineItem::kControl ||
-      type == NGInlineItem::kText)
-    return false;
-
-  if (type == NGInlineItem::kOpenTag) {
-    DCHECK(style);
-
-    if (!style->MarginStart().IsZero() || style->BorderStart().NonZero() ||
-        !style->PaddingStart().IsZero())
-      return false;
-  }
-
-  if (type == NGInlineItem::kCloseTag) {
-    DCHECK(style);
-
-    if (!style->MarginEnd().IsZero() || style->BorderEnd().NonZero() ||
-        !style->PaddingEnd().IsZero())
-      return false;
-  }
-
-  return true;
-}
-
 static void AppendItem(Vector<NGInlineItem>* items,
                        NGInlineItem::NGInlineItemType type,
                        unsigned start,
@@ -250,7 +223,7 @@ void NGInlineItemsBuilderTemplate<OffsetMappingBuilder>::
     if (last_collapsible_space_ == CollapsibleSpace::kSpace &&
         !style->AutoWrap())
       last_collapsible_space_ = CollapsibleSpace::kSpaceNoWrap;
-    is_empty_inline_ &= IsItemEmpty(NGInlineItem::kText, style);
+    is_empty_inline_ &= items_->back().IsEmptyItem();
   }
 }
 
@@ -278,7 +251,7 @@ void NGInlineItemsBuilderTemplate<OffsetMappingBuilder>::
     AppendItem(items_, NGInlineItem::kText, start_offset, text_.length(), style,
                layout_object);
 
-    is_empty_inline_ &= IsItemEmpty(NGInlineItem::kText, style);
+    is_empty_inline_ &= items_->back().IsEmptyItem();
     start = end;
   }
 
@@ -339,7 +312,7 @@ void NGInlineItemsBuilderTemplate<OffsetMappingBuilder>::Append(
   unsigned end_offset = text_.length();
   AppendItem(items_, type, end_offset - 1, end_offset, style, layout_object);
 
-  is_empty_inline_ &= IsItemEmpty(type, style);
+  is_empty_inline_ &= items_->back().IsEmptyItem();
   last_collapsible_space_ = CollapsibleSpace::kNone;
 }
 
@@ -363,7 +336,7 @@ void NGInlineItemsBuilderTemplate<OffsetMappingBuilder>::AppendOpaque(
   unsigned end_offset = text_.length();
   AppendItem(items_, type, end_offset - 1, end_offset, style, layout_object);
 
-  is_empty_inline_ &= IsItemEmpty(type, nullptr);
+  is_empty_inline_ &= items_->back().IsEmptyItem();
 }
 
 template <typename OffsetMappingBuilder>
@@ -374,7 +347,7 @@ void NGInlineItemsBuilderTemplate<OffsetMappingBuilder>::AppendOpaque(
   unsigned end_offset = text_.length();
   AppendItem(items_, type, end_offset, end_offset, style, layout_object);
 
-  is_empty_inline_ &= IsItemEmpty(type, style);
+  is_empty_inline_ &= items_->back().IsEmptyItem();
 }
 
 // Removes the collapsible newline at the end of |text_| if exists and the

third_party/WebKit/Source/core/layout/ng/inline/ng_inline_layout_algorithm.h

@@ -46,8 +46,7 @@ class CORE_EXPORT NGInlineLayoutAlgorithm final
   scoped_refptr<NGLayoutResult> Layout() override;
 
  private:
-  scoped_refptr<NGLayoutResult> LayoutEmptyInline();
-
+  unsigned PositionLeadingItems(NGExclusionSpace*);
   void PositionPendingFloats(LayoutUnit content_size, NGExclusionSpace*);
 
   bool IsHorizontalWritingMode() const { return is_horizontal_writing_mode_; }
@@ -96,7 +95,6 @@ class CORE_EXPORT NGInlineLayoutAlgorithm final
   unsigned is_horizontal_writing_mode_ : 1;
   unsigned quirks_mode_ : 1;
 
-  std::unique_ptr<NGExclusionSpace> exclusion_space_;
   Vector<NGPositionedFloat> positioned_floats_;
   Vector<scoped_refptr<NGUnpositionedFloat>> unpositioned_floats_;
 };

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

@@ -600,8 +600,13 @@ static LayoutUnit ComputeContentSize(NGInlineNode node,
   LayoutUnit result;
   while (!break_token || !break_token->IsFinished()) {
     NGLineBreaker line_breaker(node, *space, &positioned_floats,
-                               &unpositioned_floats, break_token.get());
-    if (!line_breaker.NextLine(empty_exclusion_space, &line_info))
+                               &unpositioned_floats, &empty_exclusion_space, 0u,
+                               break_token.get());
+    if (!line_breaker.NextLine(
+            NGLayoutOpportunity(
+                NGBfcOffset(),
+                NGLogicalSize({available_inline_size, NGSizeIndefinite})),
+            &line_info))
       break;
 
     break_token = line_breaker.CreateBreakToken(nullptr);

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

@@ -9,6 +9,7 @@
 #include "core/layout/ng/inline/ng_inline_node.h"
 #include "core/layout/ng/inline/ng_physical_line_box_fragment.h"
 #include "core/layout/ng/ng_exclusion_space.h"
+#include "core/layout/ng/ng_fragment.h"
 #include "core/layout/ng/ng_layout_result.h"
 #include "core/layout/ng/ng_positioned_float.h"
 
@@ -24,10 +25,31 @@ NGLineBoxFragmentBuilder::NGLineBoxFragmentBuilder(
 
 NGLineBoxFragmentBuilder::~NGLineBoxFragmentBuilder() {}
 
+void NGLineBoxFragmentBuilder::Reset() {
+  children_.clear();
+  offsets_.clear();
+  metrics_ = NGLineHeightMetrics();
+  inline_size_ = LayoutUnit();
+}
+
 NGLogicalSize NGLineBoxFragmentBuilder::Size() const {
   return {inline_size_, metrics_.LineHeight().ClampNegativeToZero()};
 }
 
+LayoutUnit NGLineBoxFragmentBuilder::ComputeBlockSize() const {
+  LayoutUnit block_size;
+  NGWritingMode writing_mode(
+      FromPlatformWritingMode(node_.Style().GetWritingMode()));
+
+  for (size_t i = 0; i < children_.size(); ++i) {
+    block_size = std::max(
+        block_size, offsets_[i].block_offset +
+                        NGFragment(writing_mode, *children_[i]).BlockSize());
+  }
+
+  return block_size;
+}
+
 const NGPhysicalFragment* NGLineBoxFragmentBuilder::Child::PhysicalFragment()
     const {
   return layout_result ? layout_result->PhysicalFragment().get()

third_party/WebKit/Source/core/layout/ng/inline/ng_line_box_fragment_builder.h

@@ -29,7 +29,10 @@ class CORE_EXPORT NGLineBoxFragmentBuilder final
                            TextDirection);
   ~NGLineBoxFragmentBuilder() override;
 
+  void Reset();
+
   NGLogicalSize Size() const final;
+  LayoutUnit ComputeBlockSize() const;
 
   void SetMetrics(const NGLineHeightMetrics&);
   const NGLineHeightMetrics& Metrics() const { return metrics_; }

third_party/WebKit/Source/core/layout/ng/inline/ng_line_breaker.h

@@ -34,19 +34,19 @@ class CORE_EXPORT NGLineBreaker {
                 const NGConstraintSpace&,
                 Vector<NGPositionedFloat>*,
                 Vector<scoped_refptr<NGUnpositionedFloat>>*,
+                NGExclusionSpace*,
+                unsigned handled_float_index,
                 const NGInlineBreakToken* = nullptr);
   ~NGLineBreaker() {}
 
   // Compute the next line break point and produces NGInlineItemResults for
   // the line.
-  bool NextLine(const NGExclusionSpace&, NGLineInfo*);
+  bool NextLine(const NGLayoutOpportunity&, NGLineInfo*);
 
   // Create an NGInlineBreakToken for the last line returned by NextLine().
   scoped_refptr<NGInlineBreakToken> CreateBreakToken(
       std::unique_ptr<const NGInlineLayoutStateStack>) const;
 
-  NGExclusionSpace* ExclusionSpace() { return line_.exclusion_space.get(); }
-
  private:
   // This struct holds information for the current line.
   struct LineData {
@@ -59,7 +59,8 @@ class CORE_EXPORT NGLineBreaker {
     // The current opportunity.
     NGLayoutOpportunity opportunity;
 
-    std::unique_ptr<NGExclusionSpace> exclusion_space;
+    LayoutUnit line_left_bfc_offset;
+    LayoutUnit line_right_bfc_offset;
 
     // We don't create "certain zero-height line boxes".
     // https://drafts.csswg.org/css2/visuren.html#phantom-line-box
@@ -72,7 +73,10 @@ class CORE_EXPORT NGLineBreaker {
     // the next line.
     bool is_after_forced_break = false;
 
-    LayoutUnit AvailableWidth() const { return opportunity.InlineSize(); }
+    LayoutUnit AvailableWidth() const {
+      DCHECK_GE(line_right_bfc_offset, line_left_bfc_offset);
+      return line_right_bfc_offset - line_left_bfc_offset;
+    }
     bool CanFit() const { return position <= AvailableWidth(); }
     bool CanFit(LayoutUnit extra) const {
       return position + extra <= AvailableWidth();
@@ -81,11 +85,7 @@ class CORE_EXPORT NGLineBreaker {
 
   void BreakLine(NGLineInfo*);
 
-  void PrepareNextLine(const NGExclusionSpace&, NGLineInfo*);
-
-  bool HasFloatsAffectingCurrentLine() const;
-  void FindNextLayoutOpportunity();
-  void FindNextLayoutOpportunityWithMinimumInlineSize(LayoutUnit);
+  void PrepareNextLine(const NGLayoutOpportunity&, NGLineInfo*);
 
   void ComputeLineLocation(NGLineInfo*) const;
 
@@ -142,9 +142,12 @@ class CORE_EXPORT NGLineBreaker {
   const NGConstraintSpace& constraint_space_;
   Vector<NGPositionedFloat>* positioned_floats_;
   Vector<scoped_refptr<NGUnpositionedFloat>>* unpositioned_floats_;
+  NGExclusionSpace* exclusion_space_;
+
   unsigned item_index_ = 0;
   unsigned offset_ = 0;
   bool previous_line_had_forced_break_ = false;
+  LayoutUnit bfc_line_offset_;
   LayoutUnit bfc_block_offset_;
   LazyLineBreakIterator break_iterator_;
   HarfBuzzShaper shaper_;
@@ -152,7 +155,7 @@ class CORE_EXPORT NGLineBreaker {
   const Hyphenation* hyphenation_ = nullptr;
 
   // Keep track of handled float items. See HandleFloat().
-  unsigned handled_floats_end_item_index_ = 0;
+  unsigned handled_floats_end_item_index_;
 
   // The current base direction for the bidi algorithm.
   // This is copied from NGInlineNode, then updated after each forced line break

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

@@ -49,8 +49,13 @@ class NGLineBreakerTest : public NGBaseLayoutAlgorithmTest {
     NGLineInfo line_info;
     while (!break_token || !break_token->IsFinished()) {
       NGLineBreaker line_breaker(node, *space, &positioned_floats,
-                                 &unpositioned_floats, break_token.get());
-      if (!line_breaker.NextLine(exclusion_space, &line_info))
+                                 &unpositioned_floats, &exclusion_space, 0u,
+                                 break_token.get());
+      if (!line_breaker.NextLine(
+              NGLayoutOpportunity(
+                  NGBfcOffset(),
+                  NGLogicalSize({available_width, NGSizeIndefinite})),
+              &line_info))
         break;
 
       break_token = line_breaker.CreateBreakToken(nullptr);

third_party/WebKit/Source/core/layout/ng/ng_exclusion_space.cc

@@ -51,6 +51,22 @@ NGLayoutOpportunity NGExclusionSpace::FindLayoutOpportunity(
   return NGLayoutOpportunity();
 }
 
+Vector<NGLayoutOpportunity> NGExclusionSpace::AllLayoutOpportunities(
+    const NGBfcOffset& offset,
+    const NGLogicalSize& available_size) const {
+  Vector<NGLayoutOpportunity> opportunities;
+  NGLayoutOpportunityIterator opportunity_iter(*this, available_size, offset);
+
+  while (true) {
+    opportunities.push_back(opportunity_iter.Next());
+
+    if (opportunity_iter.IsAtEnd())
+      break;
+  }
+
+  return opportunities;
+}
+
 LayoutUnit NGExclusionSpace::ClearanceOffset(EClear clear_type) const {
   switch (clear_type) {
     case EClear::kNone:

third_party/WebKit/Source/core/layout/ng/ng_exclusion_space.h

@@ -36,6 +36,10 @@ class CORE_EXPORT NGExclusionSpace {
       const NGLogicalSize& available_size,
       const NGLogicalSize& minimum_size) const;
 
+  Vector<NGLayoutOpportunity> AllLayoutOpportunities(
+      const NGBfcOffset& offset,
+      const NGLogicalSize& available_size) const;
+
   // Returns the clearance offset based on the provided {@code clear_type}.
   LayoutUnit ClearanceOffset(EClear clear_type) const;