Auto merge of #15929 - n0max:canvas_drawimage_crop_fix, r=nox

Fix crop_area_bytes_length calculation and add tests

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- Fix crop_area_bytes_length calculation (the height was multiplied by itself)
- Add tests for this error and for the case that the width is multiplied by itself

---
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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 #15386

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- [X] There are tests for these changes

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components/canvas/canvas_paint_thread.rs

@@ -746,7 +746,7 @@ fn crop_image(image_data: Vec<u8>,
     // (consecutive elements in a pixel row of the image are contiguous in memory)
     let stride = image_size.width * 4;
     let image_bytes_length = image_size.height * image_size.width * 4;
-    let crop_area_bytes_length = crop_rect.size.height * crop_rect.size.height * 4;
+    let crop_area_bytes_length = crop_rect.size.height * crop_rect.size.width * 4;
     // If the image size is less or equal than the crop area we do nothing
     if image_bytes_length <= crop_area_bytes_length {
         return image_data;