[css-flexbox] Implementing new CSS Box Alignment values

third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp

Index: third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp b/third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp
index 2ce5335c7c952e25732ab4126a4289b13b10babe..46c3e1665db2e76535c546e58f79773fd94fa2f7 100644
--- a/third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp
@@ -1418,9 +1418,15 @@ void LayoutFlexibleBox::alignChildren(const Vector<LineContext>& lineContexts)
                     adjustAlignmentForChild(*child, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child));
                 break;
             }
+            case ItemPositionStart:
             case ItemPositionFlexStart:
+                // We treat flex-start the same as start because alignmentForChild fixed
+                // it up appropriately
                 break;
+            case ItemPositionEnd:
             case ItemPositionFlexEnd:
+                // We treat flex-end the same as end because alignmentForChild fixed
+                // it up appropriately
                 adjustAlignmentForChild(*child, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child));
                 break;
             case ItemPositionCenter:
@@ -1437,15 +1443,30 @@ void LayoutFlexibleBox::alignChildren(const Vector<LineContext>& lineContexts)
                     minMarginAfterBaseline = std::min(minMarginAfterBaseline, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child) - startOffset);
                 break;
             }
-            case ItemPositionLastBaseline:
-            case ItemPositionSelfStart:
-            case ItemPositionSelfEnd:
-            case ItemPositionStart:
-            case ItemPositionEnd:
+            case ItemPositionSelfStart: {
+                bool hasSameCrossStartEdges = hasOrthogonalFlow(*child) ? child->styleRef().isLeftToRightDirection() == styleRef().isLeftToRightDirection() : child->styleRef().isFlippedBlocksWritingMode() == styleRef().isFlippedBlocksWritingMode();
+                if (!hasSameCrossStartEdges)
+                    adjustAlignmentForChild(*child, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child));
+                break;
+            }
+            case ItemPositionSelfEnd: {
+                bool hasSameCrossStartEdges = hasOrthogonalFlow(*child) ? child->styleRef().isLeftToRightDirection() == styleRef().isLeftToRightDirection() : child->styleRef().isFlippedBlocksWritingMode() == styleRef().isFlippedBlocksWritingMode();
+                if (hasSameCrossStartEdges)
+                    adjustAlignmentForChild(*child, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child));
+                break;
+            }
             case ItemPositionLeft:
+                // Cross-axis is only parallel to container's inline-axis when column-flow is used.
+                if (isColumnFlow() && !style()->isLeftToRightDirection())

[cbiesinger, 2015/12/01 00:12:49]

is that true? shouldn't it be if (!isHorizontalFlow() && ...) ?

same for right

+                    adjustAlignmentForChild(*child, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child));
+                break;
             case ItemPositionRight:
-                // FIXME: Implement these (https://crbug.com/507690). The extended grammar
-                // is not enabled by default so we shouldn't hit this codepath.
+                // Cross-axis is only parallel to container's inline-axis when column-flow is used.
+                if (isColumnFlow() && style()->isLeftToRightDirection())
+                    adjustAlignmentForChild(*child, availableAlignmentSpaceForChild(lineCrossAxisExtent, *child));
+                break;
+            case ItemPositionLastBaseline: // TODO (lajava): This feature is at-risk of being dropped during the CR period.

[cbiesinger, 2015/12/01 00:12:49]

if we're still parsing it, it seems better not to have an assert_not_reached
here

+            default:
                 ASSERT_NOT_REACHED();
                 break;
             }