From d4d76448d23b2034df46c9e9396e57016ea62325 Mon Sep 17 00:00:00 2001
From: stransky <stransky@redhat.com>
Date: Mon, 8 Apr 2024 09:16:40 +0000
Subject: [PATCH] Bug 1885831 [Wayland] Skip EGL window size changes and
 disable rendering of it if compositor is paused after scale change r=emilio

Skip rendering of EGL window right after scale changes. MESA backend contains old back / front buffers and we need to recreate them for new scale at ResumeCompositorFlickering().

Differential Revision: https://phabricator.services.mozilla.com/D206757
---
 widget/gtk/nsWindow.cpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/widget/gtk/nsWindow.cpp b/widget/gtk/nsWindow.cpp
index 727cdb91c322..fa2fcc03df90 100644
--- a/widget/gtk/nsWindow.cpp
+++ b/widget/gtk/nsWindow.cpp
@@ -6580,8 +6580,8 @@ void nsWindow::PauseCompositorFlickering() {
 
   CompositorBridgeChild* remoteRenderer = GetRemoteRenderer();
   if (remoteRenderer) {
-    remoteRenderer->SendPause();
     mCompositorState = COMPOSITOR_PAUSED_FLICKERING;
+    remoteRenderer->SendPause();
     mCompositorPauseTimeoutID = (int)g_timeout_add(
         COMPOSITOR_PAUSE_TIMEOUT,
         [](void* data) -> gint {
@@ -9970,6 +9970,12 @@ bool nsWindow::SetEGLNativeWindowSize(
     return true;
   }
 
+  if (mCompositorState == COMPOSITOR_PAUSED_FLICKERING) {
+    LOG("nsWindow::SetEGLNativeWindowSize() return, "
+        "COMPOSITOR_PAUSED_FLICKERING is set");
+    return false;
+  }
+
   gint scale = GdkCeiledScaleFactor();
 #  ifdef MOZ_LOGGING
   if (LOG_ENABLED()) {