[LayoutNG] Inline margin/border/padding, inter-item breaking, and tests

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

Index: third_party/WebKit/Source/core/layout/ng/ng_length_utils.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_length_utils.cc b/third_party/WebKit/Source/core/layout/ng/ng_length_utils.cc
index 95aa08381fffd84f8e8aad8b55e64a54c7854154..c059aa8d7b325d101929e7b86bc868bca5921660 100644
--- a/third_party/WebKit/Source/core/layout/ng/ng_length_utils.cc
+++ b/third_party/WebKit/Source/core/layout/ng/ng_length_utils.cc
@@ -396,6 +396,32 @@ NGBoxStrut ComputePadding(const NGConstraintSpace& constraint_space,
   return padding;
 }
 
+LayoutUnit ComputeMarginBorderPaddingInlineStart(

[cbiesinger, 2017/05/22 19:02:58]

I'd rather not add functions like these; why not use:

  (ComputeMargins() + ComputeBorders() + ComputePadding()).inline_start?

NGBoxStrut has an operator+ for that specific purpose.

[kojii, 2017/05/22 19:22:42]

It computes 4 values and discard 3 out of that. I'm ok to add 6 functions
(margin/border/padding * start/end) and the caller to sum them. Is that better?

Or is computing unnecessary 3 values ok?

[kojii, 2017/05/22 19:26:31]

BTW, you might know but in case, the legacy has MarginBorderPaddingLogicalLeft()
etc. for inline, because when inline, inline direction and block direction are
used in different phases.
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/layout/li...

+    const NGConstraintSpace& constraint_space,
+    const ComputedStyle& style) {
+  MinMaxContentSize empty_sizes;
+  return ResolveInlineLength(constraint_space, style, empty_sizes,
+                             style.MarginStart(),
+                             LengthResolveType::kMarginBorderPaddingSize) +
+         LayoutUnit(style.BorderStartWidth()) +
+         ResolveInlineLength(constraint_space, style, empty_sizes,
+                             style.PaddingStart(),
+                             LengthResolveType::kMarginBorderPaddingSize);
+}
+
+LayoutUnit ComputeMarginBorderPaddingInlineEnd(
+    const NGConstraintSpace& constraint_space,
+    const ComputedStyle& style) {
+  MinMaxContentSize empty_sizes;
+  return ResolveInlineLength(constraint_space, style, empty_sizes,
+                             style.MarginEnd(),
+                             LengthResolveType::kMarginBorderPaddingSize) +
+         LayoutUnit(style.BorderEndWidth()) +
+         ResolveInlineLength(constraint_space, style, empty_sizes,
+                             style.PaddingEnd(),
+                             LengthResolveType::kMarginBorderPaddingSize);
+}
+
 void ApplyAutoMargins(const NGConstraintSpace& constraint_space,
                       const ComputedStyle& style,
                       const LayoutUnit& inline_size,