Auto merge of #16807 - mrobinson:scroll-clamping, r=emilio

Fix clamping of scroll position in window.scrollBy

For rightward and downward overflow the spec says:

Let x be max(0, min(x, viewport scrolling area width - viewport width)).
Let y be max(0, min(y, viewport scrolling area height - viewport height)).

Previously, those operations were reversed, which created negative
overflow even when the overflow direction was downward. This change
ensures that Servo matches spec behavior.

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1 files changed, 2 insertions, 2 deletions

diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 6b8857b81b1..a2af04ad1cc 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -1066,8 +1066,8 @@ impl Window {
                 let content_size = e.upcast::<Node>().bounding_content_box_or_zero();
                 let content_height = content_size.size.height.to_f64_px();
                 let content_width = content_size.size.width.to_f64_px();
-                (xfinite.max(0.0f64).min(content_width - width),
-                 yfinite.max(0.0f64).min(content_height - height))
+                (xfinite.min(content_width - width).max(0.0f64),
+                 yfinite.min(content_height - height).max(0.0f64))
             },
             None => {
                 (xfinite.max(0.0f64), yfinite.max(0.0f64))