Removes crash keys for crbug.com/621730

blimp/engine/app/blimp_engine_crash_keys.cc

Index: blimp/engine/app/blimp_engine_crash_keys.cc
diff --git a/blimp/engine/app/blimp_engine_crash_keys.cc b/blimp/engine/app/blimp_engine_crash_keys.cc
index 928b7a79fdf6194ac767525b50b73c4126d3eac6..c51140f9c6deb83fc93cdf51ff5affcf37600816 100644
--- a/blimp/engine/app/blimp_engine_crash_keys.cc
+++ b/blimp/engine/app/blimp_engine_crash_keys.cc
@@ -67,9 +67,6 @@ size_t RegisterEngineCrashKeys() {
       { "initrf_root_process_is_live", crash_keys::kSmallSize},
       { "initrf_root_proxy_is_live", crash_keys::kSmallSize},
 
-      // Temporary for http://crbug.com/621730.
-      { "postmessage_script_info", crash_keys::kLargeSize },
-
       // Temporary for https://crbug.com/616149.
       { "existing_extension_pref_value_type", crash_keys::kSmallSize },
     };