Remove the dependency on the Garnet zip library (#5770)

assets/BUILD.gn

@@ -18,7 +18,6 @@ source_set("assets") {
     "$flutter_root/fml",
     "$flutter_root/glue",
     "//garnet/public/lib/fxl",
-    "//garnet/public/lib/zip",
   ]
 
   public_deps = [

assets/zip_asset_store.cc

@@ -18,6 +18,10 @@
 
 namespace blink {
 
+void UniqueUnzipperTraits::Free(void* file) {
+  unzClose(file);
+}
+
 ZipAssetStore::ZipAssetStore(std::string file_path)
     : file_path_(std::move(file_path)) {
   BuildStatCache();
@@ -25,8 +29,8 @@ ZipAssetStore::ZipAssetStore(std::string file_path)
 
 ZipAssetStore::~ZipAssetStore() = default;
 
-zip::UniqueUnzipper ZipAssetStore::CreateUnzipper() const {
-  return zip::UniqueUnzipper{::unzOpen2(file_path_.c_str(), nullptr)};
+UniqueUnzipper ZipAssetStore::CreateUnzipper() const {
+  return UniqueUnzipper{::unzOpen2(file_path_.c_str(), nullptr)};
 }
 
 // |blink::AssetResolver|

assets/zip_asset_store.h

@@ -10,11 +10,18 @@
 #include "flutter/assets/asset_resolver.h"
 #include "lib/fxl/macros.h"
 #include "lib/fxl/memory/ref_counted.h"
-#include "lib/zip/unique_unzipper.h"
 #include "third_party/zlib/contrib/minizip/unzip.h"
 
 namespace blink {
 
+struct UniqueUnzipperTraits {
+  static inline void* InvalidValue() { return nullptr; }
+  static inline bool IsValid(void* value) { return value != InvalidValue(); }
+  static void Free(void* file);
+};
+
+using UniqueUnzipper = fml::UniqueObject<void*, UniqueUnzipperTraits>;
+
 class ZipAssetStore final : public AssetResolver {
  public:
   ZipAssetStore(std::string file_path);
@@ -41,7 +48,7 @@ class ZipAssetStore final : public AssetResolver {
 
   void BuildStatCache();
 
-  zip::UniqueUnzipper CreateUnzipper() const;
+  UniqueUnzipper CreateUnzipper() const;
 
   FXL_DISALLOW_COPY_AND_ASSIGN(ZipAssetStore);
 };