[css-grid] Implementation of Baseline Self-Alignment

third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp

Index: third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp b/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
index 0f6faf1cc016b900853aa5e6eb43268f39611657..5c10f32b78ada371619fc75abf06b19dd1327755 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBlockFlow.cpp
@@ -2522,7 +2522,7 @@ int LayoutBlockFlow::lineCount(const RootInlineBox* stopRootInlineBox) const {
 }
 
 int LayoutBlockFlow::firstLineBoxBaseline() const {
-  if (isWritingModeRoot() && !isRubyRun())
+  if (isWritingModeRoot() && !isRubyRun() && !isGridItem())
     return -1;
   if (!childrenInline())
     return LayoutBlock::firstLineBoxBaseline();
@@ -2531,7 +2531,9 @@ int LayoutBlockFlow::firstLineBoxBaseline() const {
     DCHECK(fontData);
     if (!fontData)
       return -1;
-    return (firstLineBox()->logicalTop() +
+    return ((styleRef().isFlippedLinesWritingMode()
+                 ? logicalHeight() - firstLineBox()->logicalBottom()
+                 : firstLineBox()->logicalTop()) +
             fontData->getFontMetrics().ascent(firstRootBox()->baselineType()))
         .toInt();
   }