Bug 1652189 - SendOnStartRequestSent only for main document, r=mayhemer,necko-reviewers

Even if loadflag contains LOAD_DOCUMENT_NEEDS_COOKIE, we update cookie only for
the main documen
https://searchfox.org/mozilla-central/rev/9b282b34b5aa0f836beb735656c55efb2cc4c617/dom/ipc/ContentParent.cpp#5704

Hence, we don't need to wait for main thread IPC to proceed HttpChannelChild::OnStartRequest

Differential Revision: https://phabricator.services.mozilla.com/D84275

dom/ipc/ContentParent.cpp

@@ -5667,9 +5667,13 @@ void ContentParent::UpdateCookieStatus(nsIChannel* aChannel) {
 }
 
 nsresult ContentParent::AboutToLoadHttpFtpDocumentForChild(
-    nsIChannel* aChannel) {
+    nsIChannel* aChannel, bool* aShouldWaitForPermissionCookieUpdate) {
   MOZ_ASSERT(aChannel);
 
+  if (aShouldWaitForPermissionCookieUpdate) {
+    *aShouldWaitForPermissionCookieUpdate = false;
+  }
+
   nsresult rv;
   bool isDocument = aChannel->IsDocument();
   if (!isDocument) {
@@ -5696,6 +5700,12 @@ nsresult ContentParent::AboutToLoadHttpFtpDocumentForChild(
   rv = ssm->GetChannelResultPrincipal(aChannel, getter_AddRefs(principal));
   NS_ENSURE_SUCCESS(rv, rv);
 
+  // Let the caller know we're going to send main thread IPC for updating
+  // permisssions/cookies.
+  if (aShouldWaitForPermissionCookieUpdate) {
+    *aShouldWaitForPermissionCookieUpdate = true;
+  }
+
   TransmitBlobURLsForPrincipal(principal);
 
   rv = TransmitPermissionsForPrincipal(principal);

dom/ipc/ContentParent.h

@@ -614,7 +614,11 @@ class ContentParent final
   // HTTP(S) or FTP channel for a content process.  It is a useful place
   // to start to kick off work as early as possible in response to such
   // document loads.
-  nsresult AboutToLoadHttpFtpDocumentForChild(nsIChannel* aChannel);
+  // aShouldWaitForPermissionCookieUpdate is set to true if main thread IPCs for
+  // updating permissions/cookies are sent.
+  nsresult AboutToLoadHttpFtpDocumentForChild(
+      nsIChannel* aChannel,
+      bool* aShouldWaitForPermissionCookieUpdate = nullptr);
 
   // Send Blob URLs for this aPrincipal if they are not already known to this
   // content process and mark the process to receive any new/revoked Blob URLs

netwerk/protocol/http/HttpChannelChild.h

@@ -480,8 +480,8 @@ class HttpChannelChild final : public PHttpChannelChild,
   // True if RecvOnStartRequestSent was received.
   uint8_t mRecvOnStartRequestSentCalled : 1;
 
-  // True if this channel is suspened by waiting for permission or cookie.
-  // That is, RecvOnStartRequestSent is received.
+  // True if this channel is for a document and suspended by waiting for
+  // permission or cookie. That is, RecvOnStartRequestSent is received.
   uint8_t mSuspendedByWaitingForPermissionCookie : 1;
 
   void FinishInterceptedRedirect();

netwerk/protocol/http/HttpChannelParent.cpp

@@ -1408,18 +1408,19 @@ HttpChannelParent::OnStartRequest(nsIRequest* aRequest) {
              "HttpChannelParent getting OnStartRequest from a different "
              "HttpBaseChannel instance");*/
 
-  // Send down any permissions which are relevant to this URL if we are
+  HttpChannelOnStartRequestArgs args;
+
+  // Send down any permissions/cookies which are relevant to this URL if we are
   // performing a document load. We can't do that if mIPCClosed is set.
   if (!mIPCClosed) {
     PContentParent* pcp = Manager()->Manager();
     MOZ_ASSERT(pcp, "We should have a manager if our IPC isn't closed");
     DebugOnly<nsresult> rv =
         static_cast<ContentParent*>(pcp)->AboutToLoadHttpFtpDocumentForChild(
-            chan);
+            chan, &args.shouldWaitForOnStartRequestSent());
     MOZ_ASSERT(NS_SUCCEEDED(rv));
   }
 
-  HttpChannelOnStartRequestArgs args;
   args.multiPartID() = multiPartID;
   args.isLastPartOfMultiPart() = isLastPartOfMultiPart;
 
@@ -1537,18 +1538,6 @@ HttpChannelParent::OnStartRequest(nsIRequest* aRequest) {
     cleanedUpRequest = true;
   }
 
-  bool isDocument = chan->IsDocument();
-  if (!isDocument) {
-    rv = chan->GetIsMainDocumentChannel(&isDocument);
-    NS_ENSURE_SUCCESS(rv, rv);
-  }
-
-  nsLoadFlags loadflags;
-  chan->GetLoadFlags(&loadflags);
-  bool documentNeedsCookie = loadflags & nsIRequest::LOAD_DOCUMENT_NEEDS_COOKIE;
-
-  args.shouldWaitForOnStartRequestSent() = isDocument || documentNeedsCookie;
-
   rv = NS_OK;
 
   if (mIPCClosed ||