Flip vertical-rl coordinates for Legacy compat

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

Index: third_party/WebKit/Source/core/layout/ng/ng_block_node.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_block_node.cc b/third_party/WebKit/Source/core/layout/ng/ng_block_node.cc
index 0d365228ab5da6a1ed7311aac8cb83b1866d7882..462bb32c63aacd4ed75ddcd1319dfe630a04accf 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_block_node.cc
+++ b/third_party/WebKit/Source/core/layout/ng/ng_block_node.cc
@@ -32,7 +32,16 @@ void FragmentPositionUpdated(const NGPhysicalFragment& fragment) {
 
   DCHECK(layout_box->parent()) << "Should be called on children only.";
 
-  layout_box->setX(fragment.LeftOffset());
+  // LegacyLayout flips vertical-rl horizontal coordinates before paint.
+  // NGLayout flips X location for LegacyLayout compatibility.
+  LayoutBlock* containing_block = layout_box->containingBlock();
+  if (containing_block->styleRef().isFlippedBlocksWritingMode()) {
+    LayoutUnit container_width = containing_block->logicalHeight();

[cbiesinger, 2017/02/24 21:48:10]

I'd do size().width() instead of logicalHeight() since we use physical
coordinates in the rest of this function

[atotic, 2017/02/24 22:41:15]

done

+    layout_box->setX(container_width - fragment.LeftOffset() -
+                     fragment.Width());
+  } else {
+    layout_box->setX(fragment.LeftOffset());
+  }
   layout_box->setY(fragment.TopOffset());
 }