Refactor StringGenerator bindings

Make every dependency request explicit on what encoding is used. Also get rid of InjectRule in XjcToDomainResourceConverterTest.

Random number generator providers are separated to secure and insecure ones. The insecure ones must be explicitly requested (usually for use cases where security is not of concern, for better speed).

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=217921422

java/google/registry/config/RegistryConfig.java

@@ -28,11 +28,15 @@ import com.google.common.net.HostAndPort;
 import dagger.Module;
 import dagger.Provides;
 import google.registry.config.RegistryConfigSettings.AppEngine.ToolsServiceUrl;
+import google.registry.util.RandomStringGenerator;
+import google.registry.util.StringGenerator;
 import google.registry.util.TaskQueueUtils;
 import java.lang.annotation.Documented;
 import java.lang.annotation.Retention;
 import java.net.URI;
 import java.net.URL;
+import java.security.NoSuchAlgorithmException;
+import java.security.ProviderException;
 import java.security.SecureRandom;
 import java.util.Optional;
 import java.util.Random;
@@ -1261,14 +1265,43 @@ public final class RegistryConfig {
     }
 
     /**
-     * Returns a singleton random number generator.
+     * Returns a singleton insecure random number generator that is fast.
      *
-     * @see google.registry.util.UrlFetchUtils
+     * <p>This binding is intentionally qualified so that any requester must explicitly acknowledge
+     * that using an insecure random number generator is fine for its use case.
      */
     @Singleton
     @Provides
-    public static Random provideRandom() {
-      return new SecureRandom();
+    @Config("insecureRandom")
+    public static Random provideInsecureRandom() {
+      return new Random();
+    };
+
+    /** Returns a singleton secure random number generator this is slow. */
+    @Singleton
+    @Provides
+    public static SecureRandom provideSecureRandom() {
+      try {
+        return SecureRandom.getInstance("NativePRNG");
+      } catch (NoSuchAlgorithmException e) {
+        throw new ProviderException(e);
+      }
+    }
+
+    /** Returns a singleton random string generator using Base58 encoding. */
+    @Singleton
+    @Provides
+    @Config("base58StringGenerator")
+    public static StringGenerator provideBase58StringGenerator(SecureRandom secureRandom) {
+      return new RandomStringGenerator(StringGenerator.Alphabets.BASE_58, secureRandom);
+    }
+
+    /** Returns a singleton random string generator using Base58 encoding. */
+    @Singleton
+    @Provides
+    @Config("base64StringGenerator")
+    public static StringGenerator provideBase64StringGenerator(SecureRandom secureRandom) {
+      return new RandomStringGenerator(StringGenerator.Alphabets.BASE_64, secureRandom);
     }
   }