Auto merge of #21048 - cbrewster:hash_change_history, r=asajeffrey

Track hash changes in session history

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Adds tracking of hash changes in the session history.

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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 #14970 fix #13437 (github issue number if applicable).

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- [ ] These changes do not require tests because _____

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1 files changed, 3 insertions, 0 deletions

diff --git a/components/script_traits/script_msg.rs b/components/script_traits/script_msg.rs
index 4487cb10d5d..762300827c8 100644
--- a/components/script_traits/script_msg.rs
+++ b/components/script_traits/script_msg.rs
@@ -116,6 +116,8 @@ pub enum ScriptMsg {
     AbortLoadUrl,
     /// Post a message to the currently active window of a given browsing context.
     PostMessage(BrowsingContextId, Option<ImmutableOrigin>, Vec<u8>),
+    /// Inform the constellation that a fragment was navigated to and whether or not it was a replacement navigation.
+    NavigatedToFragment(ServoUrl, bool),
     /// HTMLIFrameElement Forward or Back traversal.
     TraverseHistory(TraversalDirection),
     /// Inform the constellation of a pushed history state.
@@ -184,6 +186,7 @@ impl fmt::Debug for ScriptMsg {
             LoadUrl(..) => "LoadUrl",
             AbortLoadUrl => "AbortLoadUrl",
             PostMessage(..) => "PostMessage",
+            NavigatedToFragment(..) => "NavigatedToFragment",
             TraverseHistory(..) => "TraverseHistory",
             PushHistoryState(..) => "PushHistoryState",
             ReplaceHistoryState(..) => "ReplaceHistoryState",