Scroll from script should trigger a reflow

Scrolling from script should flow layout and send a display list to
WebRender. This allows all of the scroll nodes to exist in WebRender
before asking it to move the node.

See https://gist.github.com/paulirish/5d52fb081b3570c81e3a.
Fixes #29659.

20 files changed, 70 insertions, 101 deletions

diff --git a/tests/wpt/metadata-layout-2020/css/css-position/positon-absolute-scrollable-overflow-001.html.ini b/tests/wpt/metadata-layout-2020/css/css-position/positon-absolute-scrollable-overflow-001.html.ini
index 2931576e0c5..9293d969cdb 100644
--- a/tests/wpt/metadata-layout-2020/css/css-position/positon-absolute-scrollable-overflow-001.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/css-position/positon-absolute-scrollable-overflow-001.html.ini
@@ -11,12 +11,6 @@
   [.containing-block 4]
     expected: FAIL
 
-  [.containing-block 5]
-    expected: FAIL
-
-  [.containing-block 6]
-    expected: FAIL
-
   [.containing-block 7]
     expected: FAIL
 
@@ -32,11 +26,17 @@
   [.containing-block 11]
     expected: FAIL
 
-  [.containing-block 12]
+  [.containing-block 14]
     expected: FAIL
 
-  [.containing-block 13]
+  [.containing-block 5]
     expected: FAIL
 
-  [.containing-block 14]
+  [.containing-block 6]
+    expected: FAIL
+
+  [.containing-block 12]
+    expected: FAIL
+
+  [.containing-block 13]
     expected: FAIL
diff --git a/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-escape-scroller-002.html.ini b/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-escape-scroller-002.html.ini
deleted file mode 100644
index 46487c6701a..00000000000
--- a/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-escape-scroller-002.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[position-sticky-escape-scroller-002.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-overflow-padding.html.ini b/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-overflow-padding.html.ini
index 1dea93847b7..7fb4bc0467c 100644
--- a/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-overflow-padding.html.ini
+++ b/tests/wpt/metadata-layout-2020/css/css-position/sticky/position-sticky-overflow-padding.html.ini
@@ -1,6 +1,6 @@
 [position-sticky-overflow-padding.html]
-  [A sticky element should be offset by ancestor padding even when stuck]
+  [Ancestor overflow padding does not allow a sticky element to escape its container]
     expected: FAIL
 
-  [Ancestor overflow padding does not allow a sticky element to escape its container]
+  [A sticky element should be offset by ancestor padding even when stuck]
     expected: FAIL
diff --git a/tests/wpt/metadata-layout-2020/css/css-position/z-index-blend-will-change-overlapping-layers.html.ini b/tests/wpt/metadata-layout-2020/css/css-position/z-index-blend-will-change-overlapping-layers.html.ini
deleted file mode 100644
index 07353055bf7..00000000000
--- a/tests/wpt/metadata-layout-2020/css/css-position/z-index-blend-will-change-overlapping-layers.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[z-index-blend-will-change-overlapping-layers.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/CSS2/floats-clear/clear-on-parent-and-child.html.ini b/tests/wpt/metadata/css/CSS2/floats-clear/clear-on-parent-and-child.html.ini
deleted file mode 100644
index c9c1672a96f..00000000000
--- a/tests/wpt/metadata/css/CSS2/floats-clear/clear-on-parent-and-child.html.ini
+++ /dev/null
@@ -1,3 +0,0 @@
-[clear-on-parent-and-child.html]
-  bug: https://github.com/servo/webrender/issues/3078
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-backgrounds/background-attachment-local/attachment-local-positioning-2.html.ini b/tests/wpt/metadata/css/css-backgrounds/background-attachment-local/attachment-local-positioning-2.html.ini
deleted file mode 100644
index 953bbeabcbf..00000000000
--- a/tests/wpt/metadata/css/css-backgrounds/background-attachment-local/attachment-local-positioning-2.html.ini
+++ /dev/null
@@ -1,3 +0,0 @@
-[attachment-local-positioning-2.html]
-  bug: https://github.com/servo/webrender/issues/3078
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-backgrounds/background-attachment-local/attachment-scroll-positioning-1.html.ini b/tests/wpt/metadata/css/css-backgrounds/background-attachment-local/attachment-scroll-positioning-1.html.ini
deleted file mode 100644
index beea55d7dc0..00000000000
--- a/tests/wpt/metadata/css/css-backgrounds/background-attachment-local/attachment-scroll-positioning-1.html.ini
+++ /dev/null
@@ -1,3 +0,0 @@
-[attachment-scroll-positioning-1.html]
-  bug: https://github.com/servo/webrender/issues/3078
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-backgrounds/scroll-positioned-multiple-background-images.html.ini b/tests/wpt/metadata/css/css-backgrounds/scroll-positioned-multiple-background-images.html.ini
deleted file mode 100644
index 08321c4b311..00000000000
--- a/tests/wpt/metadata/css/css-backgrounds/scroll-positioned-multiple-background-images.html.ini
+++ /dev/null
@@ -1,3 +0,0 @@
-[scroll-positioned-multiple-background-images.html]
-  bug: https://github.com/servo/webrender/issues/3078
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/containing-block-change-scrollframe.html.ini b/tests/wpt/metadata/css/css-position/containing-block-change-scrollframe.html.ini
deleted file mode 100644
index 242f79c08a9..00000000000
--- a/tests/wpt/metadata/css/css-position/containing-block-change-scrollframe.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[containing-block-change-scrollframe.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-001.html.ini b/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-001.html.ini
deleted file mode 100644
index 3018d79f1af..00000000000
--- a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-001.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[position-sticky-escape-scroller-001.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-002.html.ini b/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-002.html.ini
deleted file mode 100644
index 46487c6701a..00000000000
--- a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-002.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[position-sticky-escape-scroller-002.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-003.html.ini b/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-003.html.ini
deleted file mode 100644
index 990a7ae58c6..00000000000
--- a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-003.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[position-sticky-escape-scroller-003.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-004.html.ini b/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-004.html.ini
deleted file mode 100644
index 7b98776c5e0..00000000000
--- a/tests/wpt/metadata/css/css-position/sticky/position-sticky-escape-scroller-004.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[position-sticky-escape-scroller-004.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/sticky/position-sticky-rendering.html.ini b/tests/wpt/metadata/css/css-position/sticky/position-sticky-rendering.html.ini
new file mode 100644
index 00000000000..2831b2eabe7
--- /dev/null
+++ b/tests/wpt/metadata/css/css-position/sticky/position-sticky-rendering.html.ini
@@ -0,0 +1,2 @@
+[position-sticky-rendering.html]
+  expected: FAIL
diff --git a/tests/wpt/metadata/css/css-position/z-index-blend-will-change-overlapping-layers.html.ini b/tests/wpt/metadata/css/css-position/z-index-blend-will-change-overlapping-layers.html.ini
deleted file mode 100644
index 07353055bf7..00000000000
--- a/tests/wpt/metadata/css/css-position/z-index-blend-will-change-overlapping-layers.html.ini
+++ /dev/null
@@ -1,2 +0,0 @@
-[z-index-blend-will-change-overlapping-layers.html]
-  expected: FAIL
diff --git a/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini b/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini
deleted file mode 100644
index f18b8d2fcf9..00000000000
--- a/tests/wpt/metadata/css/cssom-view/CaretPosition-001.html.ini
+++ /dev/null
@@ -1,3 +0,0 @@
-[CaretPosition-001.html]
-  [Element at (400, 100)]
-    expected: FAIL
diff --git a/tests/wpt/metadata/css/cssom-view/elementScroll-002.html.ini b/tests/wpt/metadata/css/cssom-view/elementScroll-002.html.ini
index 79b250394da..5f07b905cfb 100644
--- a/tests/wpt/metadata/css/cssom-view/elementScroll-002.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/elementScroll-002.html.ini
@@ -4,4 +4,3 @@
 
   [simple scroll with style: 'padding' and 'overflow: scroll']
     expected: FAIL
-
diff --git a/tests/wpt/metadata/css/cssom-view/scroll-behavior-default-css.html.ini b/tests/wpt/metadata/css/cssom-view/scroll-behavior-default-css.html.ini
index 6885818c71a..b084797a43f 100644
--- a/tests/wpt/metadata/css/cssom-view/scroll-behavior-default-css.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/scroll-behavior-default-css.html.ini
@@ -2,8 +2,8 @@
   [Testing default value of scroll-behavior]
     expected: FAIL
 
-  [Instant scrolling of an element with default scroll-behavior]
+  [Smooth scrolling of an element with default scroll-behavior]
     expected: FAIL
 
-  [Smooth scrolling of an element with default scroll-behavior]
+  [Instant scrolling of an element with default scroll-behavior]
     expected: FAIL
diff --git a/tests/wpt/metadata/css/cssom-view/scroll-behavior-element.html.ini b/tests/wpt/metadata/css/cssom-view/scroll-behavior-element.html.ini
index 5d579f4716f..e477e663110 100644
--- a/tests/wpt/metadata/css/cssom-view/scroll-behavior-element.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/scroll-behavior-element.html.ini
@@ -2,112 +2,112 @@
   [Testing scrollOptions' behavior for Element.scroll* and scroll-behavior on an element]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scroll() with default behavior]
+  [Element with auto scroll-behavior ; scroll() with smooth behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scroll() with auto behavior]
+  [Element with smooth scroll-behavior ; scroll() with default behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scroll() with instant behavior]
+  [Element with smooth scroll-behavior ; scroll() with auto behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scroll() with smooth behavior]
+  [Element with smooth scroll-behavior ; scroll() with smooth behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scroll() with default behavior]
+  [Element with auto scroll-behavior ; scrollTo() with smooth behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scroll() with auto behavior]
+  [Element with smooth scroll-behavior ; scrollTo() with default behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scroll() with instant behavior]
+  [Element with smooth scroll-behavior ; scrollTo() with auto behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scroll() with smooth behavior]
+  [Element with smooth scroll-behavior ; scrollTo() with smooth behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollTo() with default behavior]
+  [Element with auto scroll-behavior ; scrollBy() with smooth behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollTo() with auto behavior]
+  [Element with smooth scroll-behavior ; scrollBy() with default behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollTo() with instant behavior]
+  [Element with smooth scroll-behavior ; scrollBy() with auto behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollTo() with smooth behavior]
+  [Element with smooth scroll-behavior ; scrollBy() with smooth behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollTo() with default behavior]
+  [Element with auto scroll-behavior ; scrollIntoView() with default behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollTo() with auto behavior]
+  [Element with auto scroll-behavior ; scrollIntoView() with auto behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollTo() with instant behavior]
+  [Element with auto scroll-behavior ; scrollIntoView() with instant behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollTo() with smooth behavior]
+  [Element with auto scroll-behavior ; scrollIntoView() with smooth behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollBy() with default behavior]
+  [Element with smooth scroll-behavior ; scrollIntoView() with default behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollBy() with auto behavior]
+  [Element with smooth scroll-behavior ; scrollIntoView() with auto behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollBy() with instant behavior]
+  [Element with smooth scroll-behavior ; scrollIntoView() with instant behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollBy() with smooth behavior]
+  [Element with smooth scroll-behavior ; scrollIntoView() with smooth behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollBy() with default behavior]
+  [Set scrollLeft to element with smooth scroll-behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollBy() with auto behavior]
+  [Set scrollTop to element with smooth scroll-behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollBy() with instant behavior]
+  [Element with auto scroll-behavior ; scroll() with default behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollBy() with smooth behavior]
+  [Element with auto scroll-behavior ; scroll() with auto behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollIntoView() with default behavior]
+  [Element with auto scroll-behavior ; scroll() with instant behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollIntoView() with auto behavior]
+  [Element with smooth scroll-behavior ; scroll() with instant behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollIntoView() with instant behavior]
+  [Element with auto scroll-behavior ; scrollTo() with default behavior]
     expected: FAIL
 
-  [Element with auto scroll-behavior ; scrollIntoView() with smooth behavior]
+  [Element with auto scroll-behavior ; scrollTo() with auto behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollIntoView() with default behavior]
+  [Element with auto scroll-behavior ; scrollTo() with instant behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollIntoView() with auto behavior]
+  [Element with smooth scroll-behavior ; scrollTo() with instant behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollIntoView() with instant behavior]
+  [Element with auto scroll-behavior ; scrollBy() with default behavior]
     expected: FAIL
 
-  [Element with smooth scroll-behavior ; scrollIntoView() with smooth behavior]
+  [Element with auto scroll-behavior ; scrollBy() with auto behavior]
     expected: FAIL
 
-  [Set scrollLeft to element with auto scroll-behavior]
+  [Element with auto scroll-behavior ; scrollBy() with instant behavior]
     expected: FAIL
 
-  [Set scrollLeft to element with smooth scroll-behavior]
+  [Element with smooth scroll-behavior ; scrollBy() with instant behavior]
     expected: FAIL
 
-  [Set scrollTop to element with auto scroll-behavior]
+  [Set scrollLeft to element with auto scroll-behavior]
     expected: FAIL
 
-  [Set scrollTop to element with smooth scroll-behavior]
+  [Set scrollTop to element with auto scroll-behavior]
     expected: FAIL
 
   [Aborting an ongoing smooth scrolling on an element with another smooth scrolling]
diff --git a/tests/wpt/metadata/css/cssom-view/scroll-behavior-smooth-positions.html.ini b/tests/wpt/metadata/css/cssom-view/scroll-behavior-smooth-positions.html.ini
index b74bb322d1f..c436513c82b 100644
--- a/tests/wpt/metadata/css/cssom-view/scroll-behavior-smooth-positions.html.ini
+++ b/tests/wpt/metadata/css/cssom-view/scroll-behavior-smooth-positions.html.ini
@@ -2,66 +2,65 @@
   [Scroll positions when performing smooth scrolling from (1000, 0) to (500, 250) using scrollIntoView() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scrollTo() ]
-    expected: FAIL
-
   [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scrollIntoView() ]
     expected: FAIL
 
   [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scrollIntoView() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scrollTo() ]
-    expected: FAIL
-
   [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scrollIntoView() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scrollBy() ]
+  [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scroll() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (1000, 0) to (500, 250) using scrollBy() ]
+  [Scroll positions when performing smooth scrolling from (1000, 0) to (500, 250) using scroll() ]
     expected: FAIL
 
-  [Scroll positions when aborting a smooth scrolling with an instant scrolling]
+  [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scroll() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scrollBy() ]
+  [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scroll() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (1000, 0) to (500, 250) using scroll() ]
+  [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scrollTo() ]
     expected: FAIL
 
   [Scroll positions when performing smooth scrolling from (1000, 0) to (500, 250) using scrollTo() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scroll() ]
+  [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scrollTo() ]
     expected: FAIL
 
-  [Scroll positions when aborting a smooth scrolling with another smooth scrolling]
+  [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scrollTo() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scroll() ]
+  [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scrollBy() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scroll() ]
+  [Scroll positions when performing smooth scrolling from (1000, 0) to (500, 250) using scrollBy() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scrollTo() ]
+  [Scroll positions when performing smooth scrolling from (0, 500) to (500, 250) using scrollBy() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from (0, 0) to (500, 250) using scrollBy() ]
+  [Scroll positions when performing smooth scrolling from (1000, 500) to (500, 250) using scrollBy() ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from 500 to 250 by setting scrollTop ]
+  [Scroll positions when performing smooth scrolling from 0 to 500 by setting scrollLeft ]
     expected: FAIL
 
   [Scroll positions when performing smooth scrolling from 1000 to 500 by setting scrollLeft ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from 0 to 500 by setting scrollLeft ]
+  [Scroll positions when performing smooth scrolling from 0 to 250 by setting scrollTop ]
     expected: FAIL
 
-  [Scroll positions when performing smooth scrolling from 0 to 250 by setting scrollTop ]
+  [Scroll positions when performing smooth scrolling from 500 to 250 by setting scrollTop ]
     expected: FAIL
 
+  [Scroll positions when aborting a smooth scrolling with another smooth scrolling]
+    expected: FAIL
+
+  [Scroll positions when aborting a smooth scrolling with an instant scrolling]
+    expected: FAIL