aconfig: remove extra new lines and spaces in generated java code

Change the java template to remove the extra new lines and spaces
in generated java code.

Bug: 280833463
Test: atest aconfig.test
Change-Id: I336050540f8a2b0966bf21cf6e034a8fa701458e
diff --git a/tools/aconfig/templates/Flags.java.template b/tools/aconfig/templates/Flags.java.template
index eef98eb..c244b15 100644
--- a/tools/aconfig/templates/Flags.java.template
+++ b/tools/aconfig/templates/Flags.java.template
@@ -1,15 +1,15 @@
 package {package_name};
 
 public final class Flags \{
-    {{- for item in class_elements}}
+{{- for item in class_elements}}
     public static final String FLAG_{item.flag_name_constant_suffix} = "{item.device_config_flag}";
-    {{- endfor }}
-    {{ for item in class_elements}}
+{{- endfor }}
+{{ for item in class_elements}}
     public static boolean {item.method_name}() \{
         return FEATURE_FLAGS.{item.method_name}();
     }
-    {{ endfor }}
-    {{ if is_test_mode }}
+{{ endfor }}
+{{ -if is_test_mode }}
     public static void setFeatureFlagsImpl(FeatureFlags featureFlags) \{
         Flags.FEATURE_FLAGS = featureFlags;
     }
@@ -17,8 +17,7 @@
     public static void unsetFeatureFlagsImpl() \{
         Flags.FEATURE_FLAGS = null;
     }
-    {{ -endif}}
-
+{{ endif}}
     private static FeatureFlags FEATURE_FLAGS{{ -if not is_test_mode }} = new FeatureFlagsImpl(){{ -endif- }};
 
 }