ziparchive: add a std::string_view overload to Next.

Recovery wanted this, and frameworks/base/ wants it too.

Bug: http://b/129068177
Test: treehugger
Change-Id: I8ee3f7c058fc9c1cde829da613ed15be5ce7b41e
diff --git a/libziparchive/zip_archive.cc b/libziparchive/zip_archive.cc
index f4b6c74..e966295 100644
--- a/libziparchive/zip_archive.cc
+++ b/libziparchive/zip_archive.cc
@@ -748,10 +748,19 @@
 }
 
 int32_t Next(void* cookie, ZipEntry* data, std::string* name) {
+  std::string_view sv;
+  int32_t result = Next(cookie, data, &sv);
+  if (result == 0 && name) {
+    *name = std::string(sv);
+  }
+  return result;
+}
+
+int32_t Next(void* cookie, ZipEntry* data, std::string_view* name) {
   ZipString zs;
   int32_t result = Next(cookie, data, &zs);
-  if (result == 0) {
-    *name = std::string(reinterpret_cast<const char*>(zs.name), zs.name_length);
+  if (result == 0 && name) {
+    *name = std::string_view(reinterpret_cast<const char*>(zs.name), zs.name_length);
   }
   return result;
 }