Capture transaction traces before system reboot

Bug: 299937754
Test: bugreport - data/misc/wmtrace/systemRestart_transactions.winscope
Test: go/winscope
Change-Id: Icfb10a9e69fd2ca7f4657564b109f8da126f7dc7
diff --git a/libs/gui/SurfaceComposerClient.cpp b/libs/gui/SurfaceComposerClient.cpp
index 3743025..1977ce6 100644
--- a/libs/gui/SurfaceComposerClient.cpp
+++ b/libs/gui/SurfaceComposerClient.cpp
@@ -3113,6 +3113,10 @@
             ->removeWindowInfosListener(windowInfosListener,
                                         ComposerServiceAIDL::getComposerService());
 }
+
+void SurfaceComposerClient::notifyShutdown() {
+    ComposerServiceAIDL::getComposerService()->notifyShutdown();
+}
 // ----------------------------------------------------------------------------
 
 status_t ScreenshotClient::captureDisplay(const DisplayCaptureArgs& captureArgs,