Revert "Auto merge of #24677 - jdm:iframe-sizing-cleanup, r=asajeffrey"jdm-revert4

This reverts commit 9a518cf7979b79b34611135d09c1dd0a96945255, reversing
changes made to a33d493a4ff6f8a629a9b82202c49c41ecbefa49.

1 files changed, 18 insertions, 3 deletions

diff --git a/components/compositing/compositor.rs b/components/compositing/compositor.rs
index 3df7e1a8a0c..94f578d48f1 100644
--- a/components/compositing/compositor.rs
+++ b/components/compositing/compositor.rs
@@ -209,6 +209,9 @@ pub struct IOCompositor<Window: WindowMethods + ?Sized> {
 
     /// True to translate mouse input into touch events.
     convert_mouse_to_touch: bool,
+
+    /// Ratio of device pixels per px at the default scale.
+    device_pixels_per_px: Option<f32>,
 }
 
 #[derive(Clone, Copy)]
@@ -281,6 +284,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
         is_running_problem_test: bool,
         exit_after_load: bool,
         convert_mouse_to_touch: bool,
+        device_pixels_per_px: Option<f32>,
     ) -> Self {
         let composite_target = match output_file {
             Some(_) => CompositeTarget::PngFile,
@@ -323,6 +327,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             is_running_problem_test,
             exit_after_load,
             convert_mouse_to_touch,
+            device_pixels_per_px,
         }
     }
 
@@ -333,6 +338,7 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
         is_running_problem_test: bool,
         exit_after_load: bool,
         convert_mouse_to_touch: bool,
+        device_pixels_per_px: Option<f32>,
     ) -> Self {
         let mut compositor = IOCompositor::new(
             window,
@@ -341,11 +347,15 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
             is_running_problem_test,
             exit_after_load,
             convert_mouse_to_touch,
+            device_pixels_per_px,
         );
 
         // 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
     }
 
@@ -635,6 +645,8 @@ 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();
     }
 
@@ -1069,10 +1081,13 @@ impl<Window: WindowMethods + ?Sized> IOCompositor<Window> {
     }
 
     fn hidpi_factor(&self) -> Scale<f32, DeviceIndependentPixel, DevicePixel> {
-        if self.output_file.is_some() {
-            return Scale::new(1.0);
+        match self.device_pixels_per_px {
+            Some(device_pixels_per_px) => Scale::new(device_pixels_per_px),
+            None => match self.output_file {
+                Some(_) => Scale::new(1.0),
+                None => self.embedder_coordinates.hidpi_factor,
+            },
         }
-        self.embedder_coordinates.hidpi_factor
     }
 
     fn device_pixels_per_page_px(&self) -> Scale<f32, CSSPixel, DevicePixel> {