Auto merge of #11890 - shinglyu:viewport-percent-recalc, r=mbrubeck

Bug 10104 - Only restyle nodes that uses viewport percentage units on viewport size change

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Bug 10104 - Only restyle nodes that uses viewport percentage units on viewport size change
---
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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 #10104 (github issue number if applicable).

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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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1 files changed, 3 insertions, 1 deletions

diff --git a/components/script/dom/node.rs b/components/script/dom/node.rs
index 5cb2ac540c4..37495be3ba3 100644
--- a/components/script/dom/node.rs
+++ b/components/script/dom/node.rs
@@ -159,7 +159,9 @@ bitflags! {
         const SEQUENTIALLY_FOCUSABLE = 0x20,
 
         /// Whether any ancestor is a fragmentation container
-        const CAN_BE_FRAGMENTED = 0x40
+        const CAN_BE_FRAGMENTED = 0x40,
+        #[doc = "Specifies whether this node needs to be dirted when viewport size changed."]
+        const DIRTY_ON_VIEWPORT_SIZE_CHANGE = 0x80
     }
 }