Add ScopedAllowSyncCall to AndroidOverlay.

Bug: 1181378
Change-Id: Id6b5ad5f5a94cdc26e95b544aeb9fb490142e401
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2720010
Auto-Submit: Frank Liberato <liberato@chromium.org>
Commit-Queue: Frank Liberato <liberato@chromium.org>
Commit-Queue: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Daniel Cheng <dcheng@chromium.org>
Reviewed-by: Bo <boliu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#858427}

content/browser/android/dialog_overlay_impl.cc

@@ -13,6 +13,7 @@
 #include "content/public/browser/web_contents_delegate.h"
 #include "gpu/ipc/common/gpu_surface_tracker.h"
 #include "media/mojo/mojom/android_overlay.mojom.h"
+#include "mojo/public/cpp/bindings/sync_call_restrictions.h"
 #include "ui/android/view_android_observer.h"
 #include "ui/android/window_android.h"
 
@@ -253,6 +254,17 @@ void DialogOverlayImpl::RegisterWindowObserverIfNeeded(
   }
 }
 
+// Helper class that has permission to talk to SyncCallRestrictions.  Rather
+// than friend the function directly, which has an odd signature, friend a class
+// that knows how to do the work.
+class AndroidOverlaySyncHelper {
+ public:
+  static void MakeSyncCall(media::mojom::AndroidOverlayClient* remote) {
+    mojo::SyncCallRestrictions::ScopedAllowSyncCall scoped_allow;
+    remote->OnSynchronouslyDestroyed();
+  }
+};
+
 static void JNI_DialogOverlayImpl_NotifyDestroyedSynchronously(
     JNIEnv* env,
     int message_pipe_handle) {
@@ -262,9 +274,11 @@ static void JNI_DialogOverlayImpl_NotifyDestroyedSynchronously(
       mojo::PendingRemote<media::mojom::AndroidOverlayClient>(
           std::move(scoped_handle),
           media::mojom::AndroidOverlayClient::Version_));
+  // This prevents crashes, though it's unclear how we'd have a null remote.
+  // https://crbug.com/1155313 .
   if (!remote.is_bound())
     return;
-  remote->OnSynchronouslyDestroyed();
+  AndroidOverlaySyncHelper::MakeSyncCall(remote.get());
   // Note that we don't take back the mojo message pipe.  We let it close when
   // `remote` goes out of scope.
 }

mojo/public/cpp/bindings/sync_call_restrictions.h

@@ -21,6 +21,7 @@ class CastCdmOriginProvider;
 
 namespace content {
 class DesktopCapturerLacros;
+class AndroidOverlaySyncHelper;
 }  // namespace content
 
 namespace crosapi {
@@ -91,6 +92,9 @@ class COMPONENT_EXPORT(MOJO_CPP_BINDINGS) SyncCallRestrictions {
   // TODO(159346933) Remove once the origin isolation logic is moved outside of
   // cast media service.
   friend class chromecast::CastCdmOriginProvider;
+  // Android requires synchronous processing when overlay surfaces are
+  // destroyed, else behavior is undefined.
+  friend class content::AndroidOverlaySyncHelper;
   // END ALLOWED USAGE.
 
 #if ENABLE_SYNC_CALL_RESTRICTIONS