[LayoutNG] Allow block-flow layout to be fragmented using new approach.

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

Index: third_party/WebKit/Source/core/layout/ng/layout_ng_block_flow.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/layout_ng_block_flow.cc b/third_party/WebKit/Source/core/layout/ng/layout_ng_block_flow.cc
index 7eb001cca76aa9e5e24e4945cd80be64794b6bc2..4005385788aeed51c6aeac71427ffbc13a50d71e 100644
--- a/third_party/WebKit/Source/core/layout/ng/layout_ng_block_flow.cc
+++ b/third_party/WebKit/Source/core/layout/ng/layout_ng_block_flow.cc
@@ -27,7 +27,8 @@ void LayoutNGBlockFlow::layoutBlock(bool relayoutChildren) {
   // passes (probably FirstChild(), etc).
   m_box = new NGBlockNode(this);
 
-  RefPtr<NGLayoutResult> result = m_box->Layout(constraint_space);
+  RefPtr<NGLayoutResult> result =
+      m_box->Layout(constraint_space, /* break_token */ nullptr);

[Gleb Lanbin, 2017/02/24 21:51:27]

make break_token optional?

[ikilpatrick, 2017/02/25 00:57:21]

Done.

 
   if (isOutOfFlowPositioned()) {
     // In legacy layout, abspos differs from regular blocks in that abspos