Track libziparchive API change.

Bug: http://b/129068177
Test: treehugger
Change-Id: I618bbcf38914dd81e042e0cfd1976ff26274dc30
diff --git a/applypatch/imgdiff.cpp b/applypatch/imgdiff.cpp
index 415d95f..cb34d46 100644
--- a/applypatch/imgdiff.cpp
+++ b/applypatch/imgdiff.cpp
@@ -675,7 +675,7 @@
 // Iterate the zip entries and compose the image chunks accordingly.
 bool ZipModeImage::InitializeChunks(const std::string& filename, ZipArchiveHandle handle) {
   void* cookie;
-  int ret = StartIteration(handle, &cookie, nullptr, nullptr);
+  int ret = StartIteration(handle, &cookie);
   if (ret != 0) {
     LOG(ERROR) << "Failed to iterate over entries in " << filename << ": " << ErrorCodeString(ret);
     return false;