Bug 1666196 - Part 1: Move decision to cancel to ProcessHangMonitor. r=smaug

Differential Revision: https://phabricator.services.mozilla.com/D90825

dom/ipc/ContentParent.cpp

@@ -5602,12 +5602,6 @@ void ContentParent::CancelContentJSExecutionIfRunning(
     return;
   }
 
-  if (!aBrowserParent->CanCancelContentJS(aNavigationType,
-                                          aCancelContentJSOptions.mIndex,
-                                          aCancelContentJSOptions.mUri)) {
-    return;
-  }
-
   ProcessHangMonitor::CancelContentJSExecutionIfRunning(
       mHangMonitorActor, aBrowserParent, aNavigationType,
       aCancelContentJSOptions);

dom/ipc/ProcessHangMonitor.cpp

@@ -784,6 +784,12 @@ void HangMonitorParent::CancelContentJSExecutionIfRunning(
     const dom::CancelContentJSOptions& aCancelContentJSOptions) {
   MOZ_RELEASE_ASSERT(NS_IsMainThread());
 
+  if (!aBrowserParent->CanCancelContentJS(aNavigationType,
+                                          aCancelContentJSOptions.mIndex,
+                                          aCancelContentJSOptions.mUri)) {
+    return;
+  }
+
   TabId id = aBrowserParent->GetTabId();
   Dispatch(NewNonOwningRunnableMethod<TabId, nsIRemoteTab::NavigationType,
                                       int32_t, nsIURI*, int32_t>(