From 03be4583e0adde8c1331697a1440e9a32f1b4dcc Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Fri, 15 Apr 2016 14:15:44 -0700
Subject: [PATCH 1/2] Do not propagate floats in or out of absolutely
 positioned flows.

Fixes #10625
---
 components/layout/sequential.rs | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/components/layout/sequential.rs b/components/layout/sequential.rs
index 6ca7332497a..bc4668f33c6 100644
--- a/components/layout/sequential.rs
+++ b/components/layout/sequential.rs
@@ -9,6 +9,7 @@ use context::{LayoutContext, SharedLayoutContext};
 use display_list_builder::DisplayListBuildState;
 use euclid::point::Point2D;
 use floats::SpeculatedFloatPlacement;
+use flow::IS_ABSOLUTELY_POSITIONED;
 use flow::{PostorderFlowTraversal, PreorderFlowTraversal};
 use flow::{self, Flow, ImmutableFlowUtils, InorderFlowTraversal, MutableFlowUtils};
 use flow_ref::{self, FlowRef};
@@ -144,10 +145,15 @@ pub fn guess_float_placement(flow: &mut Flow) {
 
     let mut floats_in = SpeculatedFloatPlacement::compute_floats_in_for_first_child(flow);
     for kid in flow::mut_base(flow).child_iter_mut() {
-        floats_in.compute_floats_in(kid);
-        flow::mut_base(kid).speculated_float_placement_in = floats_in;
-        guess_float_placement(kid);
-        floats_in = flow::base(kid).speculated_float_placement_out;
+        if flow::base(kid).flags.contains(IS_ABSOLUTELY_POSITIONED) {
+            // Do not propagate floats in or out, but do propogate between kids.
+            guess_float_placement(kid);
+        } else {
+            floats_in.compute_floats_in(kid);
+            flow::mut_base(kid).speculated_float_placement_in = floats_in;
+            guess_float_placement(kid);
+            floats_in = flow::base(kid).speculated_float_placement_out;
+        }
     }
     floats_in.compute_floats_out(flow);
     flow::mut_base(flow).speculated_float_placement_out = floats_in

From 2ecadc913aaf16a4dbaaf881857448a60cac0080 Mon Sep 17 00:00:00 2001
From: Michael Howell <michael@notriddle.com>
Date: Fri, 15 Apr 2016 15:36:56 -0700
Subject: [PATCH 2/2] Add reftest for #10625

---
 tests/wpt/mozilla/meta/MANIFEST.json          | 24 +++++++++++++++++++
 .../css/absolute_line_height_after_float.html |  6 +++++
 .../absolute_line_height_after_float_ref.html |  4 ++++
 3 files changed, 34 insertions(+)
 create mode 100644 tests/wpt/mozilla/tests/css/absolute_line_height_after_float.html
 create mode 100644 tests/wpt/mozilla/tests/css/absolute_line_height_after_float_ref.html

diff --git a/tests/wpt/mozilla/meta/MANIFEST.json b/tests/wpt/mozilla/meta/MANIFEST.json
index 121842c43ff..d56fdb61efc 100644
--- a/tests/wpt/mozilla/meta/MANIFEST.json
+++ b/tests/wpt/mozilla/meta/MANIFEST.json
@@ -106,6 +106,18 @@
             "url": "/_mozilla/css/absolute_inline_containing_block_a.html"
           }
         ],
+        "css/absolute_line_height_after_float.html": [
+          {
+            "path": "css/absolute_line_height_after_float.html",
+            "references": [
+              [
+                "/_mozilla/css/absolute_line_height_after_float_ref.html",
+                "=="
+              ]
+            ],
+            "url": "/_mozilla/css/absolute_line_height_after_float.html"
+          }
+        ],
         "css/absolute_table.html": [
           {
             "path": "css/absolute_table.html",
@@ -6732,6 +6744,18 @@
           "url": "/_mozilla/css/absolute_inline_containing_block_a.html"
         }
       ],
+      "css/absolute_line_height_after_float.html": [
+        {
+          "path": "css/absolute_line_height_after_float.html",
+          "references": [
+            [
+              "/_mozilla/css/absolute_line_height_after_float_ref.html",
+              "=="
+            ]
+          ],
+          "url": "/_mozilla/css/absolute_line_height_after_float.html"
+        }
+      ],
       "css/absolute_table.html": [
         {
           "path": "css/absolute_table.html",
diff --git a/tests/wpt/mozilla/tests/css/absolute_line_height_after_float.html b/tests/wpt/mozilla/tests/css/absolute_line_height_after_float.html
new file mode 100644
index 00000000000..b8fe85ef6ec
--- /dev/null
+++ b/tests/wpt/mozilla/tests/css/absolute_line_height_after_float.html
@@ -0,0 +1,6 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Line-height should be respected after a float</title>
+<link rel="match" href="absolute_line_height_after_float_ref.html">
+<div style="float: left; padding: 0 0 0 1px;"></div>
+<span style="position: absolute; right: 0; top: 0; line-height: 100px;">X</span>
diff --git a/tests/wpt/mozilla/tests/css/absolute_line_height_after_float_ref.html b/tests/wpt/mozilla/tests/css/absolute_line_height_after_float_ref.html
new file mode 100644
index 00000000000..87b5a67edef
--- /dev/null
+++ b/tests/wpt/mozilla/tests/css/absolute_line_height_after_float_ref.html
@@ -0,0 +1,4 @@
+<!doctype html>
+<meta charset="utf-8">
+<title>Reference</title>
+<span style="position: absolute; right: 0; top: 0; line-height: 100px;">X</span>