Use empty data if file in zip has length 0

Mmap fails when the length of a file in a zip is 0, so use an
aapt::io::EmptyData when the file length is 0.

Bug: 113094267
Test: manual
Change-Id: I2c1071293bf9b0fe33e8c279c8d78ff906fba5d6
diff --git a/tools/aapt2/io/ZipArchive.cpp b/tools/aapt2/io/ZipArchive.cpp
index 8e6d713..866e96d 100644
--- a/tools/aapt2/io/ZipArchive.cpp
+++ b/tools/aapt2/io/ZipArchive.cpp
@@ -33,6 +33,11 @@
     : zip_handle_(handle), zip_entry_(entry), source_(source) {}
 
 std::unique_ptr<IData> ZipFile::OpenAsData() {
+  // The file will fail to be mmaped if it is empty
+  if (zip_entry_.uncompressed_length == 0) {
+    return util::make_unique<EmptyData>();
+  }
+
   if (zip_entry_.method == kCompressStored) {
     int fd = GetFileDescriptor(zip_handle_);