Bug 1842548 - Remove dom.ipc.cancel_content_js_when_navigating pref r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D186641

dom/ipc/BrowserHost.cpp

@@ -279,10 +279,8 @@ BrowserHost::MaybeCancelContentJSExecutionFromScript(
   if (!cancelContentJSOptions.Init(aCx, aCancelContentJSOptions)) {
     return NS_ERROR_INVALID_ARG;
   }
-  if (StaticPrefs::dom_ipc_cancel_content_js_when_navigating()) {
-    GetContentParent()->CancelContentJSExecutionIfRunning(
-        mRoot, aNavigationType, cancelContentJSOptions);
-  }
+  GetContentParent()->CancelContentJSExecutionIfRunning(mRoot, aNavigationType,
+                                                        cancelContentJSOptions);
   return NS_OK;
 }
 

dom/ipc/tests/browser_cancel_content_js.js

@@ -11,10 +11,9 @@ const TEST_PAGE =
 const NEXT_PAGE = "http://mochi.test:8888/browser/dom/ipc/tests/";
 const JS_URI = "javascript:void(document.title = 'foo')";
 
-async function test_navigation(nextPage, cancelContentJSPref, shouldCancel) {
+async function test_navigation(nextPage, shouldCancel) {
   await SpecialPowers.pushPrefEnv({
     set: [
-      ["dom.ipc.cancel_content_js_when_navigating", cancelContentJSPref],
       ["dom.max_script_run_time", 20],
       // Force a single process so that the navigation will complete in the same
       // process as the previous page which is running the long-running script.
@@ -40,11 +39,7 @@ async function test_navigation(nextPage, cancelContentJSPref, shouldCancel) {
     content.dispatchEvent(new content.Event("StartLongLoop"));
   });
 
-  info(
-    `navigating to ${nextPage} with cancel content JS ${
-      cancelContentJSPref ? "enabled" : "disabled"
-    }`
-  );
+  info(`navigating to ${nextPage}`);
   const nextPageLoaded = BrowserTestUtils.waitForContentEvent(
     tab.linkedBrowser,
     "DOMTitleChanged"
@@ -66,7 +61,5 @@ async function test_navigation(nextPage, cancelContentJSPref, shouldCancel) {
   BrowserTestUtils.removeTab(tab);
 }
 
-add_task(async () => test_navigation(NEXT_PAGE, true, true));
-add_task(async () => test_navigation(NEXT_PAGE, false, false));
-add_task(async () => test_navigation(JS_URI, true, false));
-add_task(async () => test_navigation(JS_URI, false, false));
+add_task(async () => test_navigation(NEXT_PAGE, true));
+add_task(async () => test_navigation(JS_URI, false));

modules/libpref/init/StaticPrefList.yaml

@@ -2821,11 +2821,6 @@
   value: true
   mirror: always
 
-- name: dom.ipc.cancel_content_js_when_navigating
-  type: bool
-  value: true
-  mirror: always
-
 # How often to check for CPOW timeouts (ms). CPOWs are only timed
 # out by the hang monitor.
 - name: dom.ipc.cpow.timeout