[LayoutNG] Support non-horizontal flows in Flexbox

Meaning: column containers, ortho children, and non-horizontal
writing modes

Bug: 845235
Change-Id: Iba6525752d0c14a77bc9a13cc75a484cdf3a711d
Reviewed-on: https://chromium-review.googlesource.com/c/1332247
Commit-Queue: David Grogan <dgrogan@chromium.org>
Reviewed-by: Christian Biesinger <cbiesinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#611268}

third_party/blink/renderer/core/layout/flexible_box_algorithm.h

@@ -67,6 +67,7 @@ typedef Vector<FlexItem, 8> FlexItemVector;
 class FlexItem {
  public:
   // flex_base_content_size includes scrollbar width but not border or padding.
+  // min_max_sizes is the min and max size in the main axis direction.
   FlexItem(LayoutBox*,
            LayoutUnit flex_base_content_size,
            MinMaxSize min_max_sizes,

third_party/blink/renderer/core/layout/ng/ng_flex_layout_algorithm.h

@@ -29,6 +29,18 @@ class CORE_EXPORT NGFlexLayoutAlgorithm
 
   base::Optional<MinMaxSize> ComputeMinMaxSize(
       const MinMaxSizeInput&) const override;
+
+ private:
+  // This is same method as FlexItem but we need that logic before FlexItem is
+  // constructed.
+  bool MainAxisIsInlineAxis(NGBlockNode child);
+  LayoutUnit MainAxisContentExtent(LayoutUnit sum_hypothetical_main_size);
+
+  NGLogicalSize border_box_size_;
+  NGBoxStrut border_scrollbar_padding_;
+  NGLogicalSize content_box_size_;
+  NGBoxStrut borders_;
+  NGBoxStrut padding_;
 };
 
 }  // namespace blink

third_party/blink/renderer/core/layout/ng/ng_length_utils.h

@@ -130,10 +130,11 @@ MinMaxSize ComputeMinAndMaxContentContribution(
     NGLayoutInputNode child,
     const MinMaxSizeInput& input);
 
-// Resolves the computed value in style.logicalWidth (Length) to a layout unit,
-// then constrains the result by the resolved min logical width and max logical
-// width from the ComputedStyle object. Calls Node::ComputeMinMaxSize if needed.
-// override_minmax is provided *solely* for use by unit tests.
+// Returns inline size of the node's border box by resolving the computed value
+// in style.logicalWidth (Length) to a layout unit, adding border and padding,
+// then constraining the result by the resolved min logical width and max
+// logical width from the ComputedStyle object. Calls Node::ComputeMinMaxSize if
+// needed. override_minmax is provided *solely* for use by unit tests.
 // border_padding can be passed in as an optimization; otherwise this function
 // will compute it itself.
 CORE_EXPORT LayoutUnit ComputeInlineSizeForFragment(