Auto merge of #17609 - asajeffrey:canvas-clear-state, r=jdm

Clear canvas thread state on recreation.

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The canvas rendering context is cleared when it is recreated, but not the matching state in the canvas paint thread.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #17533
- [X] These changes do not require tests because the css-paint-api tests test for this already.

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1 files changed, 2 insertions, 0 deletions

diff --git a/components/canvas/canvas_paint_thread.rs b/components/canvas/canvas_paint_thread.rs
index 68cb96cd685..344e7d18430 100644
--- a/components/canvas/canvas_paint_thread.rs
+++ b/components/canvas/canvas_paint_thread.rs
@@ -544,6 +544,8 @@ impl<'a> CanvasPaintThread<'a> {
 
     fn recreate(&mut self, size: Size2D<i32>) {
         self.drawtarget = CanvasPaintThread::create(size);
+        self.state = CanvasPaintState::new(self.state.draw_options.antialias == AntialiasMode::Default);
+        self.saved_states.clear();
         // Webrender doesn't let images change size, so we clear the webrender image key.
         if let Some(image_key) = self.image_key.take() {
             self.webrender_api.delete_image(image_key);