Fix assertion in lambda merger

Change-Id: I49a4691ce3e37b896688281d0b95f22916810546
diff --git a/src/main/java/com/android/tools/r8/ir/optimize/lambda/LambdaMerger.java b/src/main/java/com/android/tools/r8/ir/optimize/lambda/LambdaMerger.java
index 9981290..a11f309 100644
--- a/src/main/java/com/android/tools/r8/ir/optimize/lambda/LambdaMerger.java
+++ b/src/main/java/com/android/tools/r8/ir/optimize/lambda/LambdaMerger.java
@@ -434,9 +434,7 @@
             .map(method -> appView.graphLense().mapDexEncodedMethod(method, appView))
             .collect(Collectors.toSet());
     converter.processMethodsConcurrently(methods, executorService);
-    methods.forEach(method -> {
-      assert method.isProcessed();
-    });
+    assert methods.stream().allMatch(DexEncodedMethod::isProcessed);
   }
 
   private void analyzeClass(DexProgramClass clazz) {