Prefer List/NestedSet over Iterable

This is in preparation for making NestedSet not implement Iterable
anymore.

PiperOrigin-RevId: 286243512
diff --git a/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java b/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
index b77535b..b3f92ab 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/BuildView.java
@@ -675,7 +675,8 @@
     ImmutableList.Builder<Artifact> artifacts = ImmutableList.builder();
     // Add to 'artifacts' all extra-actions which were registered by aspects which 'topLevel'
     // might have injected.
-    for (Artifact.DerivedArtifact artifact : provider.getTransitiveExtraActionArtifacts()) {
+    for (Artifact.DerivedArtifact artifact :
+        provider.getTransitiveExtraActionArtifacts().toList()) {
       ActionLookupValue.ActionLookupKey owner = artifact.getArtifactOwner();
       if (owner instanceof AspectKey) {
         if (aspectClasses.contains(((AspectKey) owner).getAspectClass())) {