Flush after ResourcePool deletions complete

cc/resources/resource_pool.cc

Index: cc/resources/resource_pool.cc
diff --git a/cc/resources/resource_pool.cc b/cc/resources/resource_pool.cc
index 8041d8de46d065e1ab43029db3b1b2210b6d4e2d..61a7ae3f9fdc6519376a1b473631a73bc7cd3d40 100644
--- a/cc/resources/resource_pool.cc
+++ b/cc/resources/resource_pool.cc
@@ -410,7 +410,10 @@ void ResourcePool::EvictExpiredResources() {
   EvictResourcesNotUsedSince(current_time - resource_expiration_delay_);
 
   if (unused_resources_.empty() && busy_resources_.empty()) {
-    // Nothing is evictable.
+    // If nothing is evictable, we have deleted one (and possibly more)
+    // resources without any new activity. Flush to ensure these deletions are
+    // processed.
+    resource_provider_->FlushPendingDeletions();
     return;
   }