Remove mysql statement timeout

The mysql statement timeout just works for selects. Additionally
mysql does not support transactional rollbacks of DDL statements.
Thus there is a risk to exit in an unclean state which might cause
CC runtime errors and addtionally the timeout on selects only is not
worth much functionally.

lib/cloud_controller/db_migrator.rb

@@ -14,14 +14,14 @@ def initialize(db, max_migration_duration_in_minutes=nil, max_migration_statemen
     @db = db
     @timeout_in_minutes = default_two_weeks(max_migration_duration_in_minutes)
 
-    @max_statement_runtime_in_seconds = if max_migration_statement_runtime_in_seconds.nil? || max_migration_statement_runtime_in_seconds <= 0
-                                          30_000
-                                        else
-                                          max_migration_statement_runtime_in_seconds * 1000
-                                        end
-
-    @db.run("SET statement_timeout TO #{@max_statement_runtime_in_seconds}") if @db.database_type == :postgres
-    @db.run("SET SESSION MAX_EXECUTION_TIME=#{@max_statement_runtime_in_seconds}") if @db.database_type == :mysql
+    @max_statement_runtime_in_milliseconds = if max_migration_statement_runtime_in_seconds.nil? || max_migration_statement_runtime_in_seconds <= 0
+                                               30_000
+                                             else
+                                               max_migration_statement_runtime_in_seconds * 1000
+                                             end
+
+    @db.run("SET statement_timeout TO #{@max_statement_runtime_in_milliseconds}") if @db.database_type == :postgres
+    @db.run("SET SESSION MAX_EXECUTION_TIME=#{@max_statement_runtime_in_milliseconds}") if @db.database_type == :mysql
   end
 
   def apply_migrations(opts={})

spec/unit/lib/cloud_controller/db_migrator_spec.rb

@@ -62,18 +62,4 @@
       DBMigrator.new(db, nil, 60)
     end
   end
-
-  describe 'mysql' do
-    it 'sets a default statement select statement timeout' do
-      skip if db.database_type != :mysql
-      expect(db).to receive(:run).with('SET SESSION MAX_EXECUTION_TIME=30000')
-      DBMigrator.new(db)
-    end
-
-    it 'sets a config provided select statement timeout' do
-      skip if db.database_type != :mysql
-      expect(db).to receive(:run).with('SET SESSION MAX_EXECUTION_TIME=60000')
-      DBMigrator.new(db, nil, 60)
-    end
-  end
 end