Bug 1766132 - Use right process behaviour with BFCache in parent. r=smaug

Because we rely on the process switching code for replacing the
frameloaders for BFCache in the parent, we need to force the process
switch behaviour to PROCESS_BEHAVIOR_STANDARD if BFCache in the parent
is on.

Differential Revision: https://phabricator.services.mozilla.com/D144518

netwerk/ipc/DocumentLoadListener.cpp

@@ -1546,8 +1546,10 @@ static DocumentLoadListener::ProcessBehavior GetProcessSwitchBehavior(
   bool isRemoteBrowser = false;
   browser->GetIsRemoteBrowser(&isRemoteBrowser);
   if (isRemoteBrowser) {
-    return DocumentLoadListener::ProcessBehavior::
-        PROCESS_BEHAVIOR_SUBFRAME_ONLY;
+    return mozilla::BFCacheInParent() ? DocumentLoadListener::ProcessBehavior::
+                                            PROCESS_BEHAVIOR_STANDARD
+                                      : DocumentLoadListener::ProcessBehavior::
+                                            PROCESS_BEHAVIOR_SUBFRAME_ONLY;
   }
   return DocumentLoadListener::ProcessBehavior::PROCESS_BEHAVIOR_DISABLED;
 }