merge yshavit: Fixing an assert in TypeId.getPrecision.
merge yshavit: Fixing an assert in TypeId.getPrecision.

https://code.launchpad.net/~yshavit/akiban-sql-parser/TypeId-getPrecision_fixassert/+merge/126791
gnubila-france/sql-parser,puneetjaiswal/sql-parser,brosander/sql-parser,fivetran/sql-parser,mattyb149/sql-parser,storyeah/sql-parser,puneetjaiswal/sql-parser,brosander/sql-parser,storyeah/sql-parser,xiexingguang/sql-parser,rimig/sql-parser,cswaroop/sql-parser,hudak/sql-parser,fengshao0907/sql-parser