Collapse whitespace away when creating whitespace layout objects.

third_party/WebKit/Source/core/dom/Text.cpp

Index: third_party/WebKit/Source/core/dom/Text.cpp
diff --git a/third_party/WebKit/Source/core/dom/Text.cpp b/third_party/WebKit/Source/core/dom/Text.cpp
index f69b8552c899c41d59a2d26db83f4be95856723f..e34a38417bc776002d59c866bc88a719fc19265f 100644
--- a/third_party/WebKit/Source/core/dom/Text.cpp
+++ b/third_party/WebKit/Source/core/dom/Text.cpp
@@ -252,6 +252,11 @@ static inline bool canHaveWhitespaceChildren(const LayoutObject& parent) {
   return true;
 }
 
+static inline bool emptyOrEndsWithWhitespace(const WTF::String& string) {
+  unsigned len = string.length();
+  return !len || isASCIISpace(string[len - 1]);
+}
+
 bool Text::textLayoutObjectIsNeeded(const ComputedStyle& style,
                                     const LayoutObject& parent) const {
   DCHECK(!document().childNeedsDistributionRecalc());
@@ -290,9 +295,21 @@ bool Text::textLayoutObjectIsNeeded(const ComputedStyle& style,
   const LayoutObject* prev =
       LayoutTreeBuilderTraversal::previousSiblingLayoutObject(
           *this, maxSiblingsToVisit);
+
+  while (prev && prev->isOutOfFlowPositioned() && --maxSiblingsToVisit)
+    prev = prev->previousSibling();
+
+  if (!maxSiblingsToVisit)
+    return true;
+
   if (prev && prev->isBR())  // <span><br/> <br/></span>
     return false;
 
+  // Collapse whitespace away.
+  if (prev && prev->isText() &&
+      emptyOrEndsWithWhitespace(toLayoutText(prev)->text()))
+    return false;
+
   if (parent.isLayoutInline()) {
     // <span><div/> <div/></span>
     if (prev && !prev->isInline() && !prev->isOutOfFlowPositioned())

[rune, 2017/02/28 09:59:46]

prev cannot be out-of-flow at this point since prev is not modified after the
while-loop you added.