Bug 1790188 - Fix releasing CompositableRef of mLatestTextureHost r=lsalzman

Differential Revision: https://phabricator.services.mozilla.com/D157067

gfx/layers/RemoteTextureMap.cpp

@@ -209,6 +209,7 @@ void RemoteTextureMap::KeepTextureDataAliveForTextureHostIfNecessary(
 void RemoteTextureMap::UnregisterTextureOwner(
     const RemoteTextureOwnerId aOwnerId, const base::ProcessId aForPid) {
   UniquePtr<TextureOwner> releasingOwner;  // Release outside the mutex
+  RefPtr<TextureHost> releasingTexture;    // Release outside the mutex
   {
     MutexAutoLock lock(mMutex);
 
@@ -219,6 +220,12 @@ void RemoteTextureMap::UnregisterTextureOwner(
       return;
     }
 
+    if (it->second->mLatestTextureHost) {
+      // Release CompositableRef in mMutex
+      releasingTexture = it->second->mLatestTextureHost;
+      it->second->mLatestTextureHost = nullptr;
+    }
+
     KeepTextureDataAliveForTextureHostIfNecessary(
         lock, it->second->mUsingTextureDataHolders);
 
@@ -233,6 +240,8 @@ void RemoteTextureMap::UnregisterTextureOwners(
     const base::ProcessId aForPid) {
   std::vector<UniquePtr<TextureOwner>>
       releasingOwners;  // Release outside the mutex
+  std::vector<RefPtr<TextureHost>>
+      releasingTextures;  // Release outside the mutex
   {
     MutexAutoLock lock(mMutex);
 
@@ -244,6 +253,12 @@ void RemoteTextureMap::UnregisterTextureOwners(
         continue;
       }
 
+      if (it->second->mLatestTextureHost) {
+        // Release CompositableRef in mMutex
+        releasingTextures.emplace_back(it->second->mLatestTextureHost);
+        it->second->mLatestTextureHost = nullptr;
+      }
+
       KeepTextureDataAliveForTextureHostIfNecessary(
           lock, it->second->mUsingTextureDataHolders);