[line-clamp][IFC] Line with 0px constrain should still be considered as a non-empty line if it has content

https://bugs.webkit.org/show_bug.cgi?id=248882

Reviewed by Antti Koivisto.

Just because lineLogicalRect is empty (width: 0px;) it does not necessarily mean it has no (overflowing) content.

* LayoutTests/fast/block/zero-width-block-with-line-clamp-multiple-lines-expected.html: Added.
* LayoutTests/fast/block/zero-width-block-with-line-clamp-multiple-lines.html: Added.
* Source/WebCore/layout/formattingContexts/inline/InlineFormattingContext.cpp:
(WebCore::Layout::InlineFormattingContext::lineLayout):

Canonical link: https://commits.webkit.org/257528@main

Author: alanbaradlay

LayoutTests/fast/block/zero-width-block-with-line-clamp-multiple-lines-expected.html

@@ -0,0 +1,9 @@
+<style>
+.ellipsis {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  width: 30px;
+}
+</style>
+<div class=ellipsis>PASS</div>
+<div style="width: 0px">if only the first line has ellipsis</div>

LayoutTests/fast/block/zero-width-block-with-line-clamp-multiple-lines.html

@@ -0,0 +1,9 @@
+<style>
+div {
+  display: -webkit-box;
+  -webkit-line-clamp: 1;
+  -webkit-box-orient: vertical;
+  width: 0px;
+}
+</style>
+<div>PASS if only the first line has ellipsis</div>

Source/WebCore/layout/formattingContexts/inline/InlineFormattingContext.cpp

@@ -266,7 +266,7 @@ void InlineFormattingContext::lineLayout(InlineItems& inlineItems, const LineBui
             break;
         }
 
-        if (!lineContent.runs.isEmpty() && !lineLogicalRect.isEmpty())
+        if (!lineContent.runs.isEmpty() && lineContent.contentLogicalWidth)
             ++numberOfLines;
         lineLogicalTop = formattingGeometry().logicalTopForNextLine(lineContent, lineLogicalRect, floatingContext);
         previousLine = LineBuilder::PreviousLine { !lineContent.runs.isEmpty() && lineContent.runs.last().isLineBreak(), lineContent.inlineBaseDirection, lineContent.partialOverflowingContent, WTFMove(lineContent.overflowingFloats), lineContent.trailingOverflowingContentWidth };