Enforce RAW compression for PVer4 hash prefixes

components/safe_browsing_db/v4_update_protocol_manager.cc

Index: components/safe_browsing_db/v4_update_protocol_manager.cc
diff --git a/components/safe_browsing_db/v4_update_protocol_manager.cc b/components/safe_browsing_db/v4_update_protocol_manager.cc
index a67c4071110dee3e88a72ac19f65f985539b751c..dc994413969716ddd9e6d9f40fb3d0c06a60153b 100644
--- a/components/safe_browsing_db/v4_update_protocol_manager.cc
+++ b/components/safe_browsing_db/v4_update_protocol_manager.cc
@@ -210,6 +210,10 @@ std::string V4UpdateProtocolManager::GetBase64SerializedUpdateRequestProto(
     if (!state.empty()) {
       list_update_request->set_state(state);
     }
+
+    // TODO(vakh): Accept other compression formats also.
+    // See: https://bugs.chromium.org/p/chromium/issues/detail?id=624567
+    list_update_request->mutable_constraints()->add_supported_compressions(RAW);
   }
 
   // Serialize and Base64 encode.