Rename error that occurs when writing on a read

I originally named this `StatementInvalid` because that's what we do in
GitHub, but `@tenderlove` pointed out that this means apps can't test
for or explitly rescue this error. `StatementInvalid` is pretty broad so
I've renamed this to `ReadOnlyError`.

1 files changed, 1 insertions, 1 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
index 43e2f628dc..56f777f3be 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql/database_statements.rb
@@ -29,7 +29,7 @@ module ActiveRecord
         # Executes the SQL statement in the context of this connection.
         def execute(sql, name = nil)
           if preventing_writes? && write_query?(sql)
-            raise ActiveRecord::StatementInvalid, "Write query attempted while in readonly mode: #{sql}"
+            raise ActiveRecord::ReadOnlyError, "Write query attempted while in readonly mode: #{sql}"
           end
 
           # make sure we carry over any changes to ActiveRecord::Base.default_timezone that have been