Ensure layout/script always have a correct viewport size when a new pipeline is created.

components/compositing/compositor.rs

@@ -346,9 +346,6 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
         // Set the size of the root layer.
         compositor.update_zoom_transform();
 
-        // Tell the constellation about the initial window size.
-        compositor.send_window_size(WindowSizeType::Initial);
-
         compositor
     }
 
@@ -638,8 +635,6 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
 
         self.create_pipeline_details_for_frame_tree(&frame_tree);
 
-        self.send_window_size(WindowSizeType::Initial);
-
         self.frame_tree_id.next();
     }
 

components/constellation/constellation.rs

@@ -2216,6 +2216,7 @@ where
             new_pipeline_id: new_pipeline_id,
             replace: None,
             new_browsing_context_info: None,
+            window_size,
         });
     }
 
@@ -2360,6 +2361,7 @@ where
                 is_private: is_private,
                 is_visible: is_visible,
             }),
+            window_size,
         });
     }
 
@@ -2531,6 +2533,10 @@ where
         // https://github.com/rust-lang/rust/issues/59159
         let browsing_context_size = browsing_context.size;
         let browsing_context_is_visible = browsing_context.is_visible;
+        debug_assert_eq!(
+            browsing_context_size,
+            load_info.window_size.initial_viewport
+        );
 
         // Create the new pipeline, attached to the parent and push to pending changes
         self.new_pipeline(
@@ -2552,6 +2558,7 @@ where
             replace: replace,
             // Browsing context for iframe already exists.
             new_browsing_context_info: None,
+            window_size: load_info.window_size.initial_viewport,
         });
     }
 
@@ -2610,6 +2617,7 @@ where
                 is_private: is_private,
                 is_visible: is_parent_visible,
             }),
+            window_size: load_info.window_size.initial_viewport,
         });
     }
 
@@ -2698,6 +2706,7 @@ where
                 is_private: is_opener_private,
                 is_visible: is_opener_visible,
             }),
+            window_size: self.window_size.initial_viewport,
         });
     }
 
@@ -2901,6 +2910,7 @@ where
                     replace,
                     // `load_url` is always invoked on an existing browsing context.
                     new_browsing_context_info: None,
+                    window_size,
                 });
                 Some(new_pipeline_id)
             },
@@ -3220,6 +3230,7 @@ where
                     replace: Some(NeedsToReload::Yes(pipeline_id, load_data)),
                     // Browsing context must exist at this point.
                     new_browsing_context_info: None,
+                    window_size,
                 });
                 return;
             },
@@ -3977,7 +3988,7 @@ where
                     change.top_level_browsing_context_id,
                     change.new_pipeline_id,
                     new_context_info.parent_pipeline_id,
-                    self.window_size.initial_viewport, //XXXjdm is this valid?
+                    change.window_size,
                     new_context_info.is_private,
                     new_context_info.is_visible,
                 );

components/constellation/session_history.rs

@@ -3,6 +3,7 @@
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
 use crate::browsingcontext::NewBrowsingContextInfo;
+use euclid::Size2D;
 use msg::constellation_msg::{
     BrowsingContextId, HistoryStateId, PipelineId, TopLevelBrowsingContextId,
 };
@@ -10,6 +11,7 @@ use script_traits::LoadData;
 use servo_url::ServoUrl;
 use std::cmp::PartialEq;
 use std::{fmt, mem};
+use style_traits::CSSPixel;
 
 /// Represents the joint session history
 /// https://html.spec.whatwg.org/multipage/#joint-session-history
@@ -122,6 +124,9 @@ pub struct SessionHistoryChange {
     /// Holds data for not-yet constructed browsing contexts that are not
     /// easily available when they need to be constructed.
     pub new_browsing_context_info: Option<NewBrowsingContextInfo>,
+
+    /// The size of the viewport for the browsing context.
+    pub window_size: Size2D<f32, CSSPixel>,
 }
 
 /// Represents a pipeline or discarded pipeline in a history entry.

components/layout_thread/lib.rs

@@ -86,13 +86,13 @@ use script_layout_interface::wrapper_traits::LayoutNode;
 use script_traits::Painter;
 use script_traits::{ConstellationControlMsg, LayoutControlMsg, LayoutMsg as ConstellationMsg};
 use script_traits::{DrawAPaintImageResult, IFrameSizeMsg, PaintWorkletError, WindowSizeType};
-use script_traits::{ScrollState, UntrustedNodeAddress};
+use script_traits::{ScrollState, UntrustedNodeAddress, WindowSizeData};
 use selectors::Element;
 use servo_arc::Arc as ServoArc;
 use servo_atoms::Atom;
 use servo_config::opts;
 use servo_config::pref;
-use servo_geometry::{DeviceIndependentPixel, MaxRect};
+use servo_geometry::MaxRect;
 use servo_url::ServoUrl;
 use std::borrow::ToOwned;
 use std::cell::{Cell, RefCell};
@@ -254,13 +254,6 @@ pub struct LayoutThread {
     /// Load web fonts synchronously to avoid non-deterministic network-driven reflows.
     load_webfonts_synchronously: bool,
 
-    /// The initial request size of the window
-    initial_window_size: Size2D<u32, DeviceIndependentPixel>,
-
-    /// The ratio of device pixels per px at the default scale.
-    /// If unspecified, will use the platform default setting.
-    device_pixels_per_px: Option<f32>,
-
     /// Dumps the display list form after a layout.
     dump_display_list: bool,
 
@@ -311,8 +304,7 @@ impl LayoutThreadFactory for LayoutThread {
         paint_time_metrics: PaintTimeMetrics,
         busy: Arc<AtomicBool>,
         load_webfonts_synchronously: bool,
-        initial_window_size: Size2D<u32, DeviceIndependentPixel>,
+        window_size: WindowSizeData,
-        device_pixels_per_px: Option<f32>,
         dump_display_list: bool,
         dump_display_list_json: bool,
         dump_style_tree: bool,
@@ -360,8 +352,7 @@ impl LayoutThreadFactory for LayoutThread {
                         paint_time_metrics,
                         busy,
                         load_webfonts_synchronously,
-                        initial_window_size,
+                        window_size,
-                        device_pixels_per_px,
                         dump_display_list,
                         dump_display_list_json,
                         dump_style_tree,
@@ -531,8 +522,7 @@ impl LayoutThread {
         paint_time_metrics: PaintTimeMetrics,
         busy: Arc<AtomicBool>,
         load_webfonts_synchronously: bool,
-        initial_window_size: Size2D<u32, DeviceIndependentPixel>,
+        window_size: WindowSizeData,
-        device_pixels_per_px: Option<f32>,
         dump_display_list: bool,
         dump_display_list_json: bool,
         dump_style_tree: bool,
@@ -542,12 +532,10 @@ impl LayoutThread {
         trace_layout: bool,
         dump_flow_tree: bool,
     ) -> LayoutThread {
-        // The device pixel ratio is incorrect (it does not have the hidpi value),
-        // but it will be set correctly when the initial reflow takes place.
         let device = Device::new(
             MediaType::screen(),
-            initial_window_size.to_f32() * Scale::new(1.0),
+            window_size.initial_viewport,
-            Scale::new(device_pixels_per_px.unwrap_or(1.0)),
+            window_size.device_pixel_ratio,
         );
 
         // Create the channel on which new animations can be sent.
@@ -622,8 +610,6 @@ impl LayoutThread {
             last_iframe_sizes: Default::default(),
             busy,
             load_webfonts_synchronously,
-            initial_window_size,
-            device_pixels_per_px,
             dump_display_list,
             dump_display_list_json,
             dump_style_tree,
@@ -954,8 +940,7 @@ impl LayoutThread {
             info.paint_time_metrics,
             info.layout_is_busy,
             self.load_webfonts_synchronously,
-            self.initial_window_size,
+            info.window_size,
-            self.device_pixels_per_px,
             self.dump_display_list,
             self.dump_display_list_json,
             self.dump_style_tree,

components/layout_thread_2020/lib.rs

@@ -67,13 +67,12 @@ use script_layout_interface::rpc::{LayoutRPC, OffsetParentResponse, StyleRespons
 use script_traits::Painter;
 use script_traits::{ConstellationControlMsg, LayoutControlMsg, LayoutMsg as ConstellationMsg};
 use script_traits::{DrawAPaintImageResult, PaintWorkletError};
-use script_traits::{ScrollState, UntrustedNodeAddress};
+use script_traits::{ScrollState, UntrustedNodeAddress, WindowSizeData};
 use selectors::Element;
 use servo_arc::Arc as ServoArc;
 use servo_atoms::Atom;
 use servo_config::opts;
 use servo_config::pref;
-use servo_geometry::DeviceIndependentPixel;
 use servo_url::ServoUrl;
 use std::cell::{Cell, RefCell};
 use std::collections::HashMap;
@@ -212,13 +211,6 @@ pub struct LayoutThread {
     /// Load web fonts synchronously to avoid non-deterministic network-driven reflows.
     load_webfonts_synchronously: bool,
 
-    /// The initial request size of the window
-    initial_window_size: Size2D<u32, DeviceIndependentPixel>,
-
-    /// The ratio of device pixels per px at the default scale.
-    /// If unspecified, will use the platform default setting.
-    device_pixels_per_px: Option<f32>,
-
     /// Emits notifications when there is a relayout.
     relayout_event: bool,
 }
@@ -246,8 +238,7 @@ impl LayoutThreadFactory for LayoutThread {
         paint_time_metrics: PaintTimeMetrics,
         busy: Arc<AtomicBool>,
         load_webfonts_synchronously: bool,
-        initial_window_size: Size2D<u32, DeviceIndependentPixel>,
+        window_size: WindowSizeData,
-        device_pixels_per_px: Option<f32>,
         _dump_display_list: bool,
         _dump_display_list_json: bool,
         _dump_style_tree: bool,
@@ -294,8 +285,7 @@ impl LayoutThreadFactory for LayoutThread {
                         paint_time_metrics,
                         busy,
                         load_webfonts_synchronously,
-                        initial_window_size,
+                        window_size,
-                        device_pixels_per_px,
                         relayout_event,
                     );
 
@@ -457,16 +447,15 @@ impl LayoutThread {
         paint_time_metrics: PaintTimeMetrics,
         busy: Arc<AtomicBool>,
         load_webfonts_synchronously: bool,
-        initial_window_size: Size2D<u32, DeviceIndependentPixel>,
+        window_size: WindowSizeData,
-        device_pixels_per_px: Option<f32>,
         relayout_event: bool,
     ) -> LayoutThread {
         // The device pixel ratio is incorrect (it does not have the hidpi value),
         // but it will be set correctly when the initial reflow takes place.
         let device = Device::new(
             MediaType::screen(),
-            initial_window_size.to_f32() * Scale::new(1.0),
+            window_size.initial_viewport,
-            Scale::new(device_pixels_per_px.unwrap_or(1.0)),
+            window_size.device_pixel_ratio,
         );
 
         // Create the channel on which new animations can be sent.
@@ -533,8 +522,6 @@ impl LayoutThread {
             paint_time_metrics: paint_time_metrics,
             busy,
             load_webfonts_synchronously,
-            initial_window_size,
-            device_pixels_per_px,
             relayout_event,
         }
     }
@@ -820,8 +807,7 @@ impl LayoutThread {
             info.paint_time_metrics,
             info.layout_is_busy,
             self.load_webfonts_synchronously,
-            self.initial_window_size,
+            info.window_size,
-            self.device_pixels_per_px,
             false, // dump_display_list
             false, // dump_display_list_json
             false, // dump_style_tree

components/layout_traits/lib.rs

@@ -10,7 +10,6 @@
 //   that these modules won't have to depend on layout.
 
 use crossbeam_channel::{Receiver, Sender};
-use euclid::Size2D;
 use gfx::font_cache_thread::FontCacheThread;
 use ipc_channel::ipc::{IpcReceiver, IpcSender};
 use metrics::PaintTimeMetrics;
@@ -19,8 +18,7 @@ use msg::constellation_msg::{BackgroundHangMonitorRegister, PipelineId};
 use net_traits::image_cache::ImageCache;
 use profile_traits::{mem, time};
 use script_traits::LayoutMsg as ConstellationMsg;
-use script_traits::{ConstellationControlMsg, LayoutControlMsg};
+use script_traits::{ConstellationControlMsg, LayoutControlMsg, WindowSizeData};
-use servo_geometry::DeviceIndependentPixel;
 use servo_url::ServoUrl;
 use std::sync::atomic::AtomicBool;
 use std::sync::Arc;
@@ -48,8 +46,7 @@ pub trait LayoutThreadFactory {
         paint_time_metrics: PaintTimeMetrics,
         busy: Arc<AtomicBool>,
         load_webfonts_synchronously: bool,
-        initial_window_size: Size2D<u32, DeviceIndependentPixel>,
+        window_size: WindowSizeData,
-        device_pixels_per_px: Option<f32>,
         dump_display_list: bool,
         dump_display_list_json: bool,
         dump_style_tree: bool,

components/script/dom/htmliframeelement.rs

@@ -190,6 +190,7 @@ impl HTMLIFrameElement {
                     load_data: load_data.clone(),
                     old_pipeline_id: old_pipeline_id,
                     sandbox: sandboxed,
+                    window_size,
                 };
                 global_scope
                     .script_to_constellation_chan()
@@ -216,6 +217,7 @@ impl HTMLIFrameElement {
                     load_data: load_data,
                     old_pipeline_id: old_pipeline_id,
                     sandbox: sandboxed,
+                    window_size,
                 };
                 global_scope
                     .script_to_constellation_chan()

components/script/script_thread.rs

@@ -2392,6 +2392,7 @@ impl ScriptThread {
                 load_data.url.clone(),
             ),
             layout_is_busy: layout_is_busy.clone(),
+            window_size,
         });
 
         // Pick a layout thread, any layout thread

components/script_layout_interface/message.rs

@@ -230,4 +230,5 @@ pub struct LayoutThreadInit {
     pub image_cache: Arc<dyn ImageCache>,
     pub paint_time_metrics: PaintTimeMetrics,
     pub layout_is_busy: Arc<AtomicBool>,
+    pub window_size: WindowSizeData,
 }

components/script_traits/lib.rs

@@ -739,6 +739,8 @@ pub struct IFrameLoadInfoWithData {
     pub old_pipeline_id: Option<PipelineId>,
     /// Sandbox type of this iframe
     pub sandbox: IFrameSandboxState,
+    /// The initial viewport size for this iframe.
+    pub window_size: WindowSizeData,
 }
 
 /// Specifies whether the script or layout thread needs to be ticked for animation.
@@ -760,7 +762,7 @@ pub struct ScrollState {
 }
 
 /// Data about the window size.
-#[derive(Clone, Copy, Debug, Deserialize, MallocSizeOf, Serialize)]
+#[derive(Clone, Copy, Debug, Deserialize, MallocSizeOf, PartialEq, Serialize)]
 pub struct WindowSizeData {
     /// The size of the initial layout viewport, before parsing an
     /// <http://www.w3.org/TR/css-device-adapt/#initial-viewport>