[LayoutNG] A different approach to multi-col.

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 b39ecf3700257db6e92fed0aa79b7cf172ef929c..be4d0d51d2ca0a7a2d356e7cc93885bc41b7b5dc 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
@@ -18,6 +18,7 @@
 #include "core/layout/ng/ng_layout_result.h"
 #include "core/layout/ng/ng_length_utils.h"
 #include "core/layout/ng/ng_min_max_content_size.h"
+#include "core/layout/ng/ng_multi_column_layout_algorithm.h"
 #include "core/layout/ng/ng_writing_mode.h"
 #include "core/paint/PaintLayer.h"
 #include "platform/RuntimeEnabledFeatures.h"
@@ -89,10 +90,17 @@ RefPtr<NGLayoutResult> NGBlockNode::Layout(NGConstraintSpace* constraint_space,
     return RunOldLayout(*constraint_space);
   }
 
-  RefPtr<NGLayoutResult> layout_result =
-      NGBlockLayoutAlgorithm(this, constraint_space,
-                             toNGBlockBreakToken(break_token))
-          .Layout();
+  RefPtr<NGLayoutResult> layout_result;
+  if (Style().specifiesColumns()) {
+    layout_result =
+        NGMultiColumnLayoutAlgorithm(this, constraint_space,
+                                     toNGBlockBreakToken(break_token))
+            .Layout();
+  } else {
+    layout_result = NGBlockLayoutAlgorithm(this, constraint_space,
+                                           toNGBlockBreakToken(break_token))
+                        .Layout();
+  }
 
   CopyFragmentDataToLayoutBox(*constraint_space, layout_result.get());
   return layout_result;