Auto merge of #8796 - cheba:zero-point, r=SimonSapin

Replaced ZERO_POINT with Point2D::zero()

This is a proposed in servo/servo#8792 clean up.

Fixes #8792.

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7 files changed, 12 insertions, 21 deletions

diff --git a/components/gfx/paint_context.rs b/components/gfx/paint_context.rs
index 33422fe076a..2f9049db39d 100644
--- a/components/gfx/paint_context.rs
+++ b/components/gfx/paint_context.rs
@@ -35,7 +35,7 @@ use std::{f32, mem, ptr};
 use style::computed_values::{border_style, filter, image_rendering, mix_blend_mode};
 use text::TextRun;
 use text::glyph::CharIndex;
-use util::geometry::{self, MAX_RECT, PagePx, ScreenPx, ZERO_POINT};
+use util::geometry::{self, MAX_RECT, PagePx, ScreenPx};
 use util::opts;
 use util::range::Range;
 
@@ -1351,7 +1351,7 @@ impl<'a> PaintContext<'a> {
                 self.draw_target.set_transform(&draw_target_transform.mul(&Matrix2D::new(0., -1.,
                                                                                          1., 0.,
                                                                                          x, y)));
-                ZERO_POINT
+                Point2D::zero()
             }
             SidewaysRight => {
                 let x = text.baseline_origin.x.to_f32_px();
@@ -1359,7 +1359,7 @@ impl<'a> PaintContext<'a> {
                 self.draw_target.set_transform(&draw_target_transform.mul(&Matrix2D::new(0., 1.,
                                                                                          -1., 0.,
                                                                                          x, y)));
-                ZERO_POINT
+                Point2D::zero()
             }
         };
 
diff --git a/components/gfx/paint_task.rs b/components/gfx/paint_task.rs
index 6a91da70089..78e7a9e6e66 100644
--- a/components/gfx/paint_task.rs
+++ b/components/gfx/paint_task.rs
@@ -34,7 +34,7 @@ use std::mem as std_mem;
 use std::sync::Arc;
 use std::sync::mpsc::{Receiver, Select, Sender, channel};
 use url::Url;
-use util::geometry::{ExpandToPixelBoundaries, ZERO_POINT};
+use util::geometry::{ExpandToPixelBoundaries};
 use util::opts;
 use util::task;
 use util::task_state;
@@ -454,7 +454,7 @@ impl<C> PaintTask<C> where C: PaintListener + Send + 'static {
         let mut properties = Vec::new();
         build_from_paint_layer(&mut properties,
                                root_paint_layer,
-                               &ZERO_POINT,
+                               &Point2D::zero(),
                                &Matrix4::identity(),
                                &Matrix4::identity(),
                                None);
diff --git a/components/layout/display_list_builder.rs b/components/layout/display_list_builder.rs
index 048177467c1..96632c5d47d 100644
--- a/components/layout/display_list_builder.rs
+++ b/components/layout/display_list_builder.rs
@@ -58,7 +58,6 @@ use style::values::specified::{AngleOrCorner, HorizontalDirection, VerticalDirec
 use table_cell::CollapsedBordersForCell;
 use url::Url;
 use util::cursor::Cursor;
-use util::geometry::ZERO_POINT;
 use util::logical_geometry::{LogicalPoint, LogicalRect, LogicalSize, WritingMode};
 use util::opts;
 use util::range::Range;
@@ -1208,7 +1207,7 @@ impl FragmentDisplayListBuilding for Fragment {
                                                   CoordinateSystem::Parent)
             }
             StackingContextCreationMode::InnerScrollWrapper => {
-                Rect::new(ZERO_POINT, base_flow.overflow.size)
+                Rect::new(Point2D::zero(), base_flow.overflow.size)
             }
         };
         let overflow = match mode {
@@ -1222,7 +1221,7 @@ impl FragmentDisplayListBuilding for Fragment {
             }
             StackingContextCreationMode::InnerScrollWrapper |
             StackingContextCreationMode::OuterScrollWrapper => {
-                Rect::new(ZERO_POINT, border_box.size)
+                Rect::new(Point2D::zero(), border_box.size)
             }
         };
 
@@ -1498,7 +1497,7 @@ impl FragmentDisplayListBuilding for Fragment {
                                        (*clip).clone()),
             box_bounds: stacking_relative_box,
             color: color.to_gfx_color(),
-            offset: ZERO_POINT,
+            offset: Point2D::zero(),
             blur_radius: blur_radius,
             spread_radius: Au(0),
             border_radius: Au(0),
diff --git a/components/layout/fragment.rs b/components/layout/fragment.rs
index 5eae8be6891..9113088889f 100644
--- a/components/layout/fragment.rs
+++ b/components/layout/fragment.rs
@@ -46,7 +46,6 @@ use text;
 use text::TextRunScanner;
 use url::Url;
 use util;
-use util::geometry::ZERO_POINT;
 use util::logical_geometry::{LogicalMargin, LogicalRect, LogicalSize, WritingMode};
 use util::range::*;
 use util::str::slice_chars;
@@ -2053,7 +2052,7 @@ impl Fragment {
             relative_containing_block_size.to_physical(relative_containing_block_mode);
         let border_box = self.border_box.to_physical(self.style.writing_mode, container_size);
         if coordinate_system == CoordinateSystem::Own && self.establishes_stacking_context() {
-            return Rect::new(ZERO_POINT, border_box.size)
+            return Rect::new(Point2D::zero(), border_box.size)
         }
 
         // FIXME(pcwalton): This can double-count relative position sometimes for inlines (e.g.
diff --git a/components/layout/query.rs b/components/layout/query.rs
index 076b972061d..68b454b4cba 100644
--- a/components/layout/query.rs
+++ b/components/layout/query.rs
@@ -29,7 +29,6 @@ use style::properties::longhands::{display, position};
 use style::properties::style_structs;
 use style::values::AuExtensionMethods;
 use util::cursor::Cursor;
-use util::geometry::ZERO_POINT;
 use util::logical_geometry::WritingMode;
 use wrapper::{LayoutNode, ThreadSafeLayoutNode};
 
@@ -487,9 +486,9 @@ pub fn process_resolved_style_request<'ln, N: LayoutNode<'ln>>(
                     flow::base(flow_ref.deref()).stacking_relative_position,
                 // TODO(dzbarsky) search parents until we find node with a flow ref.
                 // https://github.com/servo/servo/issues/8307
-                _ => ZERO_POINT
+                _ => Point2D::zero()
             }
-        }).unwrap_or(ZERO_POINT);
+        }).unwrap_or(Point2D::zero());
         let property = match *property {
             atom!("bottom") => PositionProperty::Bottom,
             atom!("top") => PositionProperty::Top,
diff --git a/components/layout/sequential.rs b/components/layout/sequential.rs
index 275f4ed0429..5f33e5f352c 100644
--- a/components/layout/sequential.rs
+++ b/components/layout/sequential.rs
@@ -17,7 +17,6 @@ use traversal::{AssignBSizesAndStoreOverflow, AssignISizes};
 use traversal::{BubbleISizes, ConstructFlows, RecalcStyleForNode};
 use traversal::{BuildDisplayList, ComputeAbsolutePositions};
 use traversal::{PostorderDomTraversal, PreorderDomTraversal};
-use util::geometry::ZERO_POINT;
 use util::opts;
 use wrapper::LayoutNode;
 
@@ -151,5 +150,5 @@ pub fn iterate_through_flow_tree_fragment_border_boxes(root: &mut FlowRef,
         }
     }
 
-    doit(flow_ref::deref_mut(root), 0, iterator, &ZERO_POINT);
+    doit(flow_ref::deref_mut(root), 0, iterator, &Point2D::zero());
 }
diff --git a/components/util/geometry.rs b/components/util/geometry.rs
index 4d89a817853..dc84d90b202 100644
--- a/components/util/geometry.rs
+++ b/components/util/geometry.rs
@@ -59,11 +59,6 @@ pub enum PagePx {}
 // originally proposed in 2002 as a standard unit of measure in Gecko.
 // See https://bugzilla.mozilla.org/show_bug.cgi?id=177805 for more info.
 
-pub static ZERO_POINT: Point2D<Au> = Point2D {
-    x: Au(0),
-    y: Au(0),
-};
-
 pub static MAX_RECT: Rect<Au> = Rect {
     origin: Point2D {
         x: Au(i32::MIN / 2),