Auto merge of #24677 - jdm:iframe-sizing-cleanup, r=asajeffrey

Ensure all iframes are sized correctly at creation

Following in the path of #22395, these commits serve several purposes:
* prevent layout instability early during iframe loads caused by a succession of resize events
* reduce the complexity of determining what actual DPI and initial window size values are being used at startup
* ensure that all documents have a correct initial viewport size at creation

These changes fix problems that were exposed by the changes in #24462 but are independent of that PR.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes

1 files changed, 5 insertions, 1 deletions

diff --git a/components/script_layout_interface/message.rs b/components/script_layout_interface/message.rs
index 01a589d53cb..fb2bac65d07 100644
--- a/components/script_layout_interface/message.rs
+++ b/components/script_layout_interface/message.rs
@@ -10,7 +10,7 @@ use euclid::default::{Point2D, Rect};
 use gfx_traits::Epoch;
 use ipc_channel::ipc::{IpcReceiver, IpcSender};
 use metrics::PaintTimeMetrics;
-use msg::constellation_msg::{BackgroundHangMonitorRegister, PipelineId};
+use msg::constellation_msg::{BackgroundHangMonitorRegister, BrowsingContextId, PipelineId};
 use net_traits::image_cache::ImageCache;
 use profile_traits::mem::ReportsChan;
 use script_traits::Painter;
@@ -128,6 +128,7 @@ pub enum QueryMsg {
     ResolvedStyleQuery(TrustedNodeAddress, Option<PseudoElement>, PropertyId),
     StyleQuery(TrustedNodeAddress),
     ElementInnerTextQuery(TrustedNodeAddress),
+    InnerWindowDimensionsQuery(BrowsingContextId),
 }
 
 /// Any query to perform with this reflow.
@@ -147,6 +148,7 @@ impl ReflowGoal {
             ReflowGoal::LayoutQuery(ref querymsg, _) => match *querymsg {
                 QueryMsg::NodesFromPointQuery(..) |
                 QueryMsg::TextIndexQuery(..) |
+                QueryMsg::InnerWindowDimensionsQuery(_) |
                 QueryMsg::ElementInnerTextQuery(_) => true,
                 QueryMsg::ContentBoxQuery(_) |
                 QueryMsg::ContentBoxesQuery(_) |
@@ -176,6 +178,7 @@ impl ReflowGoal {
                 QueryMsg::NodeScrollIdQuery(_) |
                 QueryMsg::ResolvedStyleQuery(..) |
                 QueryMsg::OffsetParentQuery(_) |
+                QueryMsg::InnerWindowDimensionsQuery(_) |
                 QueryMsg::StyleQuery(_) => false,
             },
         }
@@ -227,4 +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,
 }