[LayoutNG] Remove out_floats_for_min_max from NGLineBreaker

This patch removes |out_floats_for_min_max| from
|NGLineBreaker|. The caller instead computes the list of
unpositioned floats from |NGLineInfo::Results()|.

This change is needed for fixes for crbug.com/10118167 and
crbug.com/1001000, but does not fix them. Fixes some cases of
|ComputeContentSize()| DCHECK failures in crbug.com/976304,
but maybe not all.

|out_floats_for_min_max| was originally added in r619070
(crrev.com/c/1365984) to keep track of unpositioned floats.
But today, |NGLineInfo::Results()| has all unpositioned
floats. Furthermore, changing rewind logic for
crbug.com/10118167 caused several tests to fail because we
don't adjust |out_floats_for_min_max| when we rewind. This
patch avoids mismatch of the two lists by unifying them.

blink_perf.layout looks neutral:
https://pinpoint-dot-chromeperf.appspot.com/job/108a2986c20000
Current assumption is that looping items isn't too expensive,
but we could add a flag to |NGLineInfo| if this loop turned
out to be more expensive in some cases.

Bug: 976304, 10118167, 1001000
Change-Id: I4a5cb98f5dc6d331a699991390d7bd97ce51cd34
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1857844
Commit-Queue: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#705820}

third_party/blink/renderer/core/layout/ng/inline/ng_inline_node.cc

@@ -1692,13 +1692,9 @@ static LayoutUnit ComputeContentSize(
   MaxSizeFromMinSize max_size_from_min_size(items_data, *max_size_cache,
                                             &floats_max_size);
 
-  Vector<LayoutObject*> floats_for_min_max;
   do {
-    floats_for_min_max.Shrink(0);
-
     NGLineInfo line_info;
-    line_breaker.NextLine(input.percentage_resolution_block_size,
-                          &floats_for_min_max, &line_info);
+    line_breaker.NextLine(input.percentage_resolution_block_size, &line_info);
     if (line_info.Results().IsEmpty())
       break;
 
@@ -1708,8 +1704,13 @@ static LayoutUnit ComputeContentSize(
     DCHECK_EQ(inline_size.Round(),
               line_info.ComputeWidth().ClampNegativeToZero().Round());
 
-    for (auto* floating_object : floats_for_min_max) {
-      DCHECK(floating_object->IsFloating());
+    for (const NGInlineItemResult& item_result : line_info.Results()) {
+      DCHECK(item_result.item);
+      const NGInlineItem& item = *item_result.item;
+      if (item.Type() != NGInlineItem::kFloating)
+        continue;
+      LayoutObject* floating_object = item.GetLayoutObject();
+      DCHECK(floating_object && floating_object->IsFloating());
 
       NGBlockNode float_node(ToLayoutBox(floating_object));
       const ComputedStyle& float_style = float_node.Style();

third_party/blink/renderer/core/layout/ng/inline/ng_line_breaker.cc

@@ -323,16 +323,9 @@ void NGLineBreaker::PrepareNextLine(NGLineInfo* line_info) {
 
 void NGLineBreaker::NextLine(
     LayoutUnit percentage_resolution_block_size_for_min_max,
-    Vector<LayoutObject*>* out_floats_for_min_max,
     NGLineInfo* line_info) {
-  // out_floats_for_min_max is required for min/max and prohibited for regular
-  // content mode.
-  DCHECK(mode_ == NGLineBreakerMode::kContent || out_floats_for_min_max);
-  DCHECK(!(mode_ == NGLineBreakerMode::kContent && out_floats_for_min_max));
-
   PrepareNextLine(line_info);
-  BreakLine(percentage_resolution_block_size_for_min_max,
-            out_floats_for_min_max, line_info);
+  BreakLine(percentage_resolution_block_size_for_min_max, line_info);
   RemoveTrailingCollapsibleSpace(line_info);
 
   const NGInlineItemResults& item_results = line_info->Results();
@@ -365,7 +358,6 @@ void NGLineBreaker::NextLine(
 
 void NGLineBreaker::BreakLine(
     LayoutUnit percentage_resolution_block_size_for_min_max,
-    Vector<LayoutObject*>* out_floats_for_min_max,
     NGLineInfo* line_info) {
   DCHECK(!line_info->IsLastLine());
   const Vector<NGInlineItem>& items = Items();
@@ -422,7 +414,7 @@ void NGLineBreaker::BreakLine(
       continue;
     }
     if (item.Type() == NGInlineItem::kFloating) {
-      HandleFloat(item, out_floats_for_min_max, line_info);
+      HandleFloat(item, line_info);
       continue;
     }
     if (item.Type() == NGInlineItem::kBidiControl) {
@@ -1358,7 +1350,6 @@ void NGLineBreaker::HandleAtomicInline(
 // allowed to position a float "above" another float which has come before us
 // in the document.
 void NGLineBreaker::HandleFloat(const NGInlineItem& item,
-                                Vector<LayoutObject*>* out_floats_for_min_max,
                                 NGLineInfo* line_info) {
   // When rewind occurs, an item may be handled multiple times.
   // Since floats are put into a separate list, avoid handling same floats
@@ -1373,13 +1364,10 @@ void NGLineBreaker::HandleFloat(const NGInlineItem& item,
   item_result->can_break_after = auto_wrap_;
   MoveToNextOf(item);
 
-  // If we are currently computing our min/max-content size simply append to
-  // the unpositioned floats list and abort.
-  if (mode_ != NGLineBreakerMode::kContent) {
-    DCHECK(out_floats_for_min_max);
-    out_floats_for_min_max->push_back(item.GetLayoutObject());
+  // If we are currently computing our min/max-content size, simply append the
+  // unpositioned floats to |NGLineInfo| and abort.
+  if (mode_ != NGLineBreakerMode::kContent)
     return;
-  }
 
   // Make sure we populate the positioned_float inside the |item_result|.
   if (item_index_ <= handled_leading_floats_index_ &&

third_party/blink/renderer/core/layout/ng/inline/ng_line_breaker.h

@@ -47,7 +47,7 @@ class CORE_EXPORT NGLineBreaker {
   // Compute the next line break point and produces NGInlineItemResults for
   // the line.
   inline void NextLine(NGLineInfo* line_info) {
-    NextLine(kIndefiniteSize, nullptr, line_info);
+    NextLine(kIndefiniteSize, line_info);
   }
 
   // During the min/max size calculation we need a special percentage
@@ -56,7 +56,6 @@ class CORE_EXPORT NGLineBreaker {
   // better yet, subclass or templetize the line-breaker for Min/Max computation
   // if we can do that without incurring a performance penalty
   void NextLine(LayoutUnit percentage_resolution_block_size_for_min_max,
-                Vector<LayoutObject*>* out_floats_for_min_max,
                 NGLineInfo*);
 
   bool IsFinished() const { return item_index_ >= Items().size(); }
@@ -104,7 +103,6 @@ class CORE_EXPORT NGLineBreaker {
                                 NGLineInfo*);
 
   void BreakLine(LayoutUnit percentage_resolution_block_size_for_min_max,
-                 Vector<LayoutObject*>* out_floats_for_min_max,
                  NGLineInfo*);
   void PrepareNextLine(NGLineInfo*);
 
@@ -173,7 +171,6 @@ class CORE_EXPORT NGLineBreaker {
   bool IsAtomicInlineBeforeNoBreakSpace(
       const NGInlineItemResult& item_result) const;
   void HandleFloat(const NGInlineItem&,
-                   Vector<LayoutObject*>* out_floats_for_min_max,
                    NGLineInfo*);
 
   void HandleOpenTag(const NGInlineItem&, NGLineInfo*);