Bug 1650837 - Part 2: Add an includeParent JSProcessActor config option, r=kmag

This is similar to JSWindowActor's includeChrome option, and defaults to
'false'. If users want to also instantiate the actor in-process, they can set
this option to 'true'.

Differential Revision: https://phabricator.services.mozilla.com/D82449

Author: mystor

dom/chrome-webidl/JSProcessActor.webidl

@@ -48,6 +48,12 @@ dictionary ProcessActorOptions {
    */
   sequence<UTF8String> remoteTypes;
 
+  /**
+   * If this is set to `true`, allow this actor to be created for the parent
+   * process.
+   */
+  boolean includeParent = false;
+
   /** This fields are used for configuring individual sides of the actor. */
   ProcessActorSidedOptions parent;
   ProcessActorChildOptions child;

dom/ipc/jsactor/JSProcessActorProtocol.cpp

@@ -26,6 +26,9 @@ JSProcessActorProtocol::FromIPC(const JSProcessActorInfo& aInfo) {
   RefPtr<JSProcessActorProtocol> proto =
       new JSProcessActorProtocol(aInfo.name());
 
+  // Content processes aren't the parent process, so this flag is irrelevant and
+  // not propagated.
+  proto->mIncludeParent = false;
   proto->mRemoteTypes = aInfo.remoteTypes().Clone();
   proto->mChild.mModuleURI = aInfo.url();
   proto->mChild.mObservers = aInfo.observers().Clone();
@@ -51,6 +54,7 @@ JSProcessActorProtocol::FromWebIDLOptions(const nsACString& aName,
   MOZ_DIAGNOSTIC_ASSERT(XRE_IsParentProcess());
 
   RefPtr<JSProcessActorProtocol> proto = new JSProcessActorProtocol(aName);
+  proto->mIncludeParent = aOptions.mIncludeParent;
 
   if (aOptions.mRemoteTypes.WasPassed()) {
     MOZ_ASSERT(aOptions.mRemoteTypes.Value().Length());
@@ -136,6 +140,10 @@ bool JSProcessActorProtocol::RemoteTypePrefixMatches(
 }
 
 bool JSProcessActorProtocol::Matches(const nsACString& aRemoteType) {
+  if (!mIncludeParent && aRemoteType.IsEmpty()) {
+    return false;
+  }
+
   if (!mRemoteTypes.IsEmpty() &&
       !RemoteTypePrefixMatches(RemoteTypePrefix(aRemoteType))) {
     return false;

dom/ipc/jsactor/JSProcessActorProtocol.h

@@ -63,6 +63,7 @@ class JSProcessActorProtocol final : public JSActorProtocol,
 
   nsCString mName;
   nsTArray<nsCString> mRemoteTypes;
+  bool mIncludeParent = false;
 
   ParentSide mParent;
   ChildSide mChild;

dom/ipc/tests/JSProcessActor/head.js

@@ -33,13 +33,20 @@ function promiseNotification(aNotification) {
 }
 
 function declTest(name, cfg) {
-  let { url = "about:blank", remoteTypes, fission, test } = cfg;
+  let {
+    url = "about:blank",
+    includeParent = false,
+    remoteTypes,
+    fission,
+    test,
+  } = cfg;
 
   // Build the actor options object which will be used to register & unregister our window actor.
   let actorOptions = {
     parent: Object.assign({}, processActorOptions.parent),
     child: Object.assign({}, processActorOptions.child),
   };
+  actorOptions.includeParent = includeParent;
   if (remoteTypes !== undefined) {
     actorOptions.remoteTypes = remoteTypes;
   }