[LayoutNG] Introduces NGPhysicalConstraintSpace and makes NGConstraintSpace a "view".

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

Index: third_party/WebKit/Source/core/layout/ng/ng_physical_constraint_space.cc
diff --git a/third_party/WebKit/Source/core/layout/ng/ng_physical_constraint_space.cc b/third_party/WebKit/Source/core/layout/ng/ng_physical_constraint_space.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7397d0c6bab684914d4d8de917384c4230de7be0
--- /dev/null
+++ b/third_party/WebKit/Source/core/layout/ng/ng_physical_constraint_space.cc
@@ -0,0 +1,45 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "core/layout/ng/ng_physical_constraint_space.h"
+
+#include "core/layout/LayoutBox.h"
+#include "core/style/ComputedStyle.h"
+
+namespace blink {
+
+NGPhysicalConstraintSpace::NGPhysicalConstraintSpace()
+    : fixed_width_(0),
+      fixed_height_(0),
+      width_direction_triggers_scrollbar_(0),
+      height_direction_triggers_scrollbar_(0),
+      width_direction_fragmentation_type_(FragmentNone),
+      height_direction_fragmentation_type_(FragmentNone) {}
+
+NGPhysicalConstraintSpace::NGPhysicalConstraintSpace(
+    const NGPhysicalConstraintSpace& other)

[cbiesinger, 2016/08/25 22:22:16]

You're not copying the exclusions...?

[ikilpatrick, 2016/08/25 23:14:29]

I don't think this makes sense as for a NGDerivedCS we'll want to explicitly add
exclusions to the parent. E.g.

NGDerivedCS::AddExclusion(ex) {
  if (parent_) {
    parent_->AddExclusion(ex);
    return;
  }

  NGCS::AddExclusion(ex);
}

I.e. there should only be one source of truth?

Alt: could store a ptr to a vector instead?

[cbiesinger, 2016/08/25 23:17:59]

Oh right. Can you add a comment explaining that, so that I won't forget again?
:-)

[ikilpatrick, 2016/08/26 16:24:26]

Added comment to derived constraint space. :)

+    : fixed_width_(other.fixed_width_),
+      fixed_height_(other.fixed_height_),
+      width_direction_triggers_scrollbar_(
+          other.width_direction_triggers_scrollbar_),
+      height_direction_triggers_scrollbar_(
+          other.height_direction_triggers_scrollbar_),
+      width_direction_fragmentation_type_(
+          other.width_direction_fragmentation_type_),
+      height_direction_fragmentation_type_(
+          other.height_direction_fragmentation_type_) {}
+
+void NGPhysicalConstraintSpace::addExclusion(const NGExclusion,
+                                             unsigned options) {
+  // TODO(layout-ng): Implement.
+}
+
+DoublyLinkedList<const NGExclusion> NGPhysicalConstraintSpace::exclusions(
+    unsigned options) const {
+  DoublyLinkedList<const NGExclusion> exclusions;
+  // TODO(layout-ng): Implement.
+  return exclusions;
+}
+
+}  // namespace blink