Auto merge of #8400 - sylvesterwillis:arrow-key-scroll-on-input, r=jdm

Added call to event.PreventDefault on html text inputs and textareas.

This change should prevent page scrolling when up/down buttons are pressed within text inputs and textboxes which should resolve issue #8379.

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2 files changed, 3 insertions, 0 deletions

diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index ed409907b42..ff4492a5520 100644
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -656,6 +656,7 @@ impl VirtualMethods for HTMLInputElement {
                         }
                         RedrawSelection => {
                             self.force_relayout();
+                            event.PreventDefault();
                         }
                         Nothing => (),
                     }
diff --git a/components/script/dom/htmltextareaelement.rs b/components/script/dom/htmltextareaelement.rs
index f9735e76c15..9b3f50bf91e 100644
--- a/components/script/dom/htmltextareaelement.rs
+++ b/components/script/dom/htmltextareaelement.rs
@@ -352,9 +352,11 @@ impl VirtualMethods for HTMLTextAreaElement {
                         }
 
                         self.force_relayout();
+                        event.PreventDefault();
                     }
                     KeyReaction::RedrawSelection => {
                         self.force_relayout();
+                        event.PreventDefault();
                     }
                     KeyReaction::Nothing => (),
                 }