[LayoutNG] Correct auto margins and text-align:-webkit-foo

There were two problems:

1. We determined start/end inline margins from the direction of the
child, while we should use that of the containing block.

2. We applied alignment based on text-align:-webkit-{left,right} even if
there was an auto inline-end margin (so that we would override it).
Standard CSS declarations should take precedence over legacy HTML align
attributes (which is where text-align:-webkit-{left,center,right}
typically come from).

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_layout_tests_layout_ng
Change-Id: Ib0a22a6293b4b2b2668d09453db16b42ef9ff258
Reviewed-on: https://chromium-review.googlesource.com/922664
Commit-Queue: Morten Stenshorne <mstensho@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Reviewed-by: Christian Biesinger <cbiesinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537291}

third_party/WebKit/LayoutTests/FlagExpectations/enable-blink-features=LayoutNG

@@ -1057,8 +1057,6 @@ crbug.com/591099 external/wpt/css/CSS2/normal-flow/max-width-applies-to-005.xht
 crbug.com/591099 external/wpt/css/CSS2/normal-flow/root-box-001.xht [ Failure ]
 crbug.com/591099 external/wpt/css/CSS2/positioning/abspos-007.xht [ Failure Pass ]
 crbug.com/591099 external/wpt/css/CSS2/positioning/positioning-float-001.xht [ Pass ]
-crbug.com/591099 external/wpt/css/CSS2/positioning/relpos-calcs-004.xht [ Failure ]
-crbug.com/591099 external/wpt/css/CSS2/positioning/relpos-calcs-005.xht [ Failure ]
 crbug.com/591099 external/wpt/css/CSS2/text/text-decoration-applies-to-015.xht [ Failure ]
 crbug.com/714962 external/wpt/css/css-backgrounds/background-attachment-local/attachment-local-clipping-color-5.html [ Failure ]
 crbug.com/714962 external/wpt/css/css-backgrounds/background-attachment-local/attachment-local-clipping-image-5.html [ Failure ]
@@ -2064,7 +2062,6 @@ crbug.com/591099 external/wpt/html/infrastructure/urls/resolving-urls/query-enco
 crbug.com/591099 external/wpt/html/infrastructure/urls/resolving-urls/query-encoding/windows-1251.html [ Timeout ]
 crbug.com/591099 external/wpt/html/infrastructure/urls/resolving-urls/query-encoding/windows-1252.html [ Timeout ]
 crbug.com/591099 external/wpt/html/rendering/non-replaced-elements/flow-content-0/dialog.html [ Failure ]
-crbug.com/591099 external/wpt/html/rendering/non-replaced-elements/flow-content-0/div-align.html [ Failure ]
 crbug.com/591099 external/wpt/html/rendering/non-replaced-elements/the-fieldset-element-0/legend-block-formatting-context.html [ Failure ]
 crbug.com/591099 external/wpt/html/rendering/replaced-elements/svg-embedded-sizing/svg-in-img-auto.html [ Failure ]
 crbug.com/591099 external/wpt/html/rendering/replaced-elements/svg-embedded-sizing/svg-in-img-percentage.html [ Failure ]
@@ -2386,7 +2383,6 @@ crbug.com/591099 fast/block/margin-collapse/clear-nested-float-more-than-one-pre
 crbug.com/591099 fast/block/margin-collapse/webkit-margin-collapse-container.html [ Failure ]
 crbug.com/591099 fast/block/margin-collapse/webkit-margin-collapse-separate-position.html [ Failure ]
 crbug.com/591099 fast/block/margin-collapse/webkit-margin-collapse-siblings.html [ Failure ]
-crbug.com/591099 fast/block/margin-left-margin-right-auto.html [ Failure ]
 crbug.com/591099 fast/block/over-constrained-auto-margin.html [ Failure ]
 crbug.com/591099 fast/block/positioning/056.html [ Failure ]
 crbug.com/591099 fast/block/positioning/059.html [ Failure ]
@@ -2895,8 +2891,6 @@ crbug.com/591099 fast/css/universal-hover-quirk.html [ Failure ]
 crbug.com/591099 fast/css/unknown-pseudo-element-matching.html [ Failure ]
 crbug.com/714962 fast/css/user-drag-none.html [ Pass ]
 crbug.com/591099 fast/css/vertical-align-lengths.html [ Failure ]
-crbug.com/591099 fast/css/vertical-lr-bfc-auto-margins-beside-float.html [ Failure ]
-crbug.com/591099 fast/css/vertical-lr-table-bfc-auto-margins-beside-float.html [ Failure ]
 crbug.com/591099 fast/css/vertical-text-overflow-ellipsis-text-align-center.html [ Failure ]
 crbug.com/591099 fast/css/vertical-text-overflow-ellipsis-text-align-justify.html [ Failure ]
 crbug.com/591099 fast/css/vertical-text-overflow-ellipsis-text-align-left.html [ Failure ]
@@ -4790,7 +4784,6 @@ crbug.com/591099 fast/webgl/webgl-composite-modes-tabswitching.html [ Timeout ]
 crbug.com/591099 fast/workers/shared-worker-location.html [ Failure ]
 crbug.com/591099 fast/workers/worker-location.html [ Failure ]
 crbug.com/591099 fast/writing-mode/Kusa-Makura-background-canvas.html [ Failure ]
-crbug.com/591099 fast/writing-mode/auto-margins-across-boundaries.html [ Failure ]
 crbug.com/591099 fast/writing-mode/auto-sizing-orthogonal-flows.html [ Failure ]
 crbug.com/714962 fast/writing-mode/background-vertical-lr.html [ Failure ]
 crbug.com/591099 fast/writing-mode/background-vertical-rl.html [ Failure ]

third_party/WebKit/LayoutTests/TestExpectations

@@ -277,8 +277,6 @@ crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/normal-flow/replaced-in
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/abspos-007.xht [ Failure ]
 crbug.com/704961 [ Mac ] virtual/layout_ng/external/wpt/css/CSS2/positioning/abspos-027.xht [ Failure ]
 crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/position-relative-035.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/relpos-calcs-004.xht [ Failure ]
-crbug.com/635619 virtual/layout_ng/external/wpt/css/CSS2/positioning/relpos-calcs-005.xht [ Failure ]
 
 ### virtual/layout_ng/fast/block/basic
 crbug.com/635619 [ Mac ] virtual/layout_ng/fast/block/basic/011.html [ Failure ]
@@ -418,7 +416,6 @@ crbug.com/714962 [ Mac ] virtual/layout_ng/fast/block/float/trailing-float-with-
 
 ### virtual/layout_ng/fast/writing-mode/
 crbug.com/714962 virtual/layout_ng/fast/writing-mode/Kusa-Makura-background-canvas.html [ Failure ]
-crbug.com/714962 virtual/layout_ng/fast/writing-mode/auto-margins-across-boundaries.html [ Failure ]
 crbug.com/714962 virtual/layout_ng/fast/writing-mode/auto-sizing-orthogonal-flows.html [ Failure ]
 crbug.com/714962 virtual/layout_ng/fast/writing-mode/background-vertical-lr.html [ Failure ]
 crbug.com/714962 virtual/layout_ng/fast/writing-mode/background-vertical-rl.html [ Failure ]

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

@@ -560,19 +560,37 @@ void ApplyAutoMargins(const ComputedStyle& style,
   const LayoutUnit used_space = inline_size + margins->InlineSum();
   const LayoutUnit available_space = available_inline_size - used_space;
   if (available_space > LayoutUnit()) {
-    if ((style.MarginStart().IsAuto() && style.MarginEnd().IsAuto()) ||
-        (!style.MarginStart().IsAuto() && !style.MarginEnd().IsAuto() &&
-         containing_block_style.GetTextAlign() == ETextAlign::kWebkitCenter)) {
+    bool start_auto = style.MarginStartUsing(containing_block_style).IsAuto();
+    bool end_auto = style.MarginEndUsing(containing_block_style).IsAuto();
+    enum EBlockAlignment { kStart, kCenter, kEnd };
+    EBlockAlignment alignment;
+    if (start_auto || end_auto) {
+      alignment = start_auto ? (end_auto ? kCenter : kEnd) : kStart;
+    } else {
+      // If none of the inline margins are auto, look for -webkit- text-align
+      // values (which are really about block alignment). These are typically
+      // mapped from the legacy "align" HTML attribute.
+      switch (containing_block_style.GetTextAlign()) {
+        case ETextAlign::kWebkitLeft:
+          alignment =
+              containing_block_style.IsLeftToRightDirection() ? kStart : kEnd;
+          break;
+        case ETextAlign::kWebkitRight:
+          alignment =
+              containing_block_style.IsLeftToRightDirection() ? kEnd : kStart;
+          break;
+        case ETextAlign::kWebkitCenter:
+          alignment = kCenter;
+          break;
+        default:
+          alignment = kStart;
+          break;
+      }
+    }
+    if (alignment == kCenter)
       margins->inline_start += available_space / 2;
-    } else if (style.MarginStart().IsAuto() ||
-               (containing_block_style.IsLeftToRightDirection() &&
-                containing_block_style.GetTextAlign() ==
-                    ETextAlign::kWebkitRight) ||
-               (!containing_block_style.IsLeftToRightDirection() &&
-                containing_block_style.GetTextAlign() ==
-                    ETextAlign::kWebkitLeft)) {
+    else if (alignment == kEnd)
       margins->inline_start += available_space;
-    }
   }
   margins->inline_end =
       available_inline_size - inline_size - margins->inline_start;