Export registered domains to drive folder

The export happens in a reducer, whois instance fields all need to be serializable. The DriveConnection is therefore installed as a class variable that can be replaced with a mock during test. Class variables are not serialized. Only fields related to a particular instance are.

Note that DriveConnection is a misnomer. It is not a connection at all. It is just a thin wrapper class around the Drive service class, which provides convenient methods to write into Drive. Regardless, it cannot be serialized.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=194596695

java/google/registry/export/DriveModule.java

@@ -19,11 +19,19 @@ import com.google.api.client.http.HttpTransport;
 import com.google.api.client.json.JsonFactory;
 import com.google.api.services.drive.Drive;
 import com.google.api.services.drive.DriveScopes;
+import dagger.Component;
 import dagger.Module;
 import dagger.Provides;
 import google.registry.config.RegistryConfig.Config;
+import google.registry.config.RegistryConfig.ConfigModule;
+import google.registry.request.Modules.AppIdentityCredentialModule;
+import google.registry.request.Modules.Jackson2Module;
+import google.registry.request.Modules.UrlFetchTransportModule;
+import google.registry.request.Modules.UseAppIdentityCredentialForGoogleApisModule;
+import google.registry.storage.drive.DriveConnection;
 import java.util.Set;
 import java.util.function.Function;
+import javax.inject.Singleton;
 
 /** Dagger module for Google {@link Drive} service connection objects. */
 @Module
@@ -39,4 +47,18 @@ public final class DriveModule {
         .setApplicationName(projectId)
         .build();
   }
+
+  @Singleton
+  @Component(
+      modules = {
+        DriveModule.class,
+        UrlFetchTransportModule.class,
+        Jackson2Module.class,
+        AppIdentityCredentialModule.class,
+        UseAppIdentityCredentialForGoogleApisModule.class,
+        ConfigModule.class
+      })
+  interface DriveComponent {
+    DriveConnection driveConnection();
+  }
 }