[Sanitizer API] Reverse order for fuzzer proto file.

Reversed order of fuzzer proto file to make the corpus
files more useful.

Bug: 1116418
Change-Id: I8f2f789b014ec252a072dfbb037e543f0a39b3b4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2574636
Commit-Queue: Yifan Luo <lyf@chromium.org>
Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Cr-Commit-Position: refs/heads/master@{#833752}

third_party/blink/renderer/modules/sanitizer_api/sanitizer_config.proto

@@ -5,13 +5,13 @@
 syntax = "proto2";
 
 message SanitizerConfigProto {
-  message Elements { repeated string element = 1; }
-  repeated string allow_elements = 1;
-  repeated string block_elements = 2;
-  repeated string drop_elements = 3;
+  required string html_string = 1;
 
-  map<string, Elements> allow_attributes = 4;
-  map<string, Elements> drop_attributes = 5;
+  message Elements { repeated string element = 1; }
+  repeated string allow_elements = 2;
+  repeated string block_elements = 3;
+  repeated string drop_elements = 4;
 
-  required string html_string = 6;
+  map<string, Elements> allow_attributes = 5;
+  map<string, Elements> drop_attributes = 6;
 }