Auto merge of #12552 - ConnorGBrewster:history_interface, r=asajeffrey

History interface Go, Back, and Forward

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r? @asajeffrey

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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 #5670 (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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implement go, forward, back

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2 files changed, 19 insertions, 1 deletions

diff --git a/components/script/dom/webidls/History.webidl b/components/script/dom/webidls/History.webidl
new file mode 100644
index 00000000000..04742d52601
--- /dev/null
+++ b/components/script/dom/webidls/History.webidl
@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// enum ScrollRestoration { "auto", "manual" };
+
+// https://html.spec.whatwg.org/multipage/#the-history-interface
+[Exposed=(Window,Worker)]
+interface History {
+  // readonly attribute unsigned long length;
+  // attribute ScrollRestoration scrollRestoration;
+  // readonly attribute any state;
+  void go(optional long delta = 0);
+  void back();
+  void forward();
+  // void pushState(any data, DOMString title, optional USVString? url = null);
+  // void replaceState(any data, DOMString title, optional USVString? url = null);
+};
diff --git a/components/script/dom/webidls/Window.webidl b/components/script/dom/webidls/Window.webidl
index bda73c9479a..651c7081305 100644
--- a/components/script/dom/webidls/Window.webidl
+++ b/components/script/dom/webidls/Window.webidl
@@ -11,7 +11,7 @@
   [Unforgeable] readonly attribute Document document;
   //         attribute DOMString name;
   [/*PutForwards=href, */Unforgeable] readonly attribute Location location;
-  //readonly attribute History history;
+  readonly attribute History history;
   //[Replaceable] readonly attribute BarProp locationbar;
   //[Replaceable] readonly attribute BarProp menubar;
   //[Replaceable] readonly attribute BarProp personalbar;