[layoutng] Create correct constraint spaces for children

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

Index: third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.cc b/third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.cc
index e8e441e9c6df3f30ba2eec8463317d67eb9afdec..e46e4ef1f2ca161c013435945f8cc9fbf9359c09 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.cc
+++ b/third_party/WebKit/Source/core/layout/ng/ng_block_layout_algorithm.cc
@@ -42,14 +42,22 @@ bool NGBlockLayoutAlgorithm::Layout(const NGConstraintSpace* constraint_space,
 
       LayoutUnit inline_size =
           computeInlineSizeForFragment(*constraint_space, *style_);
+      LayoutUnit adjusted_inline_size =
+          (inline_size - border_and_padding_.InlineSum()).clampNegativeToZero();

[mstensho (USE GERRIT), 2016/09/20 11:30:17]

Shouldn't computeInlineSizeForFragment() make sure that inline_size >=
border_and_padding?

[cbiesinger, 2016/09/20 13:43:37]

Good point, done.

       // TODO(layout-ng): For quirks mode, should we pass blockSize instead of
       // -1?
       LayoutUnit block_size = computeBlockSizeForFragment(
-          *constraint_space, *style_, LayoutUnit(-1));
+          *constraint_space, *style_, NGSizeIndefinite);
+      LayoutUnit adjusted_block_size(block_size);
+      if (adjusted_block_size != NGSizeIndefinite) {

[ikilpatrick, 2016/09/20 10:47:10]

is a comment here explaining what is going on worth it?

[cbiesinger, 2016/09/20 13:43:37]

Done.

+        adjusted_block_size =
+            (adjusted_block_size - border_and_padding_.BlockSum())
+                .clampNegativeToZero();
+      }
       constraint_space_for_children_ = new NGConstraintSpace(
-          *constraint_space, NGLogicalOffset(),
-          NGLogicalSize(inline_size - border_and_padding_.InlineSum(),
-                        block_size - border_and_padding_.BlockSum()));
+          FromPlatformWritingMode(style_->getWritingMode()),
+          FromPlatformDirection(style_->direction()), *constraint_space,
+          NGLogicalSize(adjusted_inline_size, adjusted_block_size));
       content_size_ = border_and_padding_.block_start;
 
       builder_ = new NGFragmentBuilder(NGPhysicalFragmentBase::FragmentBox);