Use gn_helpers to [se]serialize GN lists.

build/config/android/rules.gni

Index: build/config/android/rules.gni
diff --git a/build/config/android/rules.gni b/build/config/android/rules.gni
index facedb5f8404f2ea19fabbaae7f96ac46aef29d7..7c7f251c9a2aaa7b97c5b30cda46e58c7412a260 100644
--- a/build/config/android/rules.gni
+++ b/build/config/android/rules.gni
@@ -1195,7 +1195,7 @@ if (enable_java_templates) {
   #       ":foo_generated_enum"
   #     ]
   #     jar_excluded_patterns = [
-  #       "*/FooService.class", "*/FooService##*.class"
+  #       "*/FooService.class", "*/FooService\$*.class"
   #     ]
   #   }
   template("java_library") {
@@ -1292,7 +1292,7 @@ if (enable_java_templates) {
   #       ":foo_generated_enum"
   #     ]
   #     jar_excluded_patterns = [
-  #       "*/FooService.class", "*/FooService##*.class"
+  #       "*/FooService.class", "*/FooService\$*.class"
   #     ]
   #   }
   template("android_library") {
@@ -1315,9 +1315,9 @@ if (enable_java_templates) {
       }
       jar_excluded_patterns += [
         "*/R.class",
-        "*/R##*.class",
+        "*/R\$*.class",
         "*/Manifest.class",
-        "*/Manifest##*.class",
+        "*/Manifest\$*.class",
       ]
     }
   }