Update Protobuf3.g4

[maxwell2011]

Line 465, corrected PROTO3_LIT_DOBULE to PROTO3_LIT_DOUBLE

[kaby76]

This change is an incomplete rename. You need to change not only the defining occurrence of PROTO3_LIT_DOBULE but all applied occurrences too. https://github.com/antlr/grammars-v4/actions/runs/7683358509/job/20942992775?pr=3949#step:24:61

(The build should be changed to treat warnings as errors, but it would break a good number of grammars.)

Also, there seem to be a dozen or so useless parentheses in the grammar that never got cleaned up with the addition of the string literal lexer rules/folding (#2090).

$ bash /c/Users/Kenne/Documents/GitHub/g4-scripts/find-useless-parentheses.sh
CSharp 0 Protobuf3.g4 success 0.0494654
running parser and computing useless parentheses.
CSharp 0 Protobuf3.g4 success 0.0488163
Found useless parentheses in grammars...
Protobuf3.g4:L172:     : ident EQ (MINUS)? intLit enumValueOptions? SEMI
                                  ^
Protobuf3.g4:L229:     : RPC rpcName LP (STREAM)? messageType RP RETURNS LP (STREAM)? messageType RP (
                                        ^
Protobuf3.g4:L229:     : RPC rpcName LP (STREAM)? messageType RP RETURNS LP (STREAM)? messageType RP (
                                                                            ^
Protobuf3.g4:L295:     : (DOT)? (ident DOT)* messageName
                         ^
Protobuf3.g4:L299:     : (DOT)? (ident DOT)* enumName
                         ^
Protobuf3.g4:L532:     : ('\'' ( CHAR_VALUE)*? '\'')
                         ^
Protobuf3.g4:L532:     : ('\'' ( CHAR_VALUE)*? '\'')
                               ^
Protobuf3.g4:L533:     | ( '"' ( CHAR_VALUE)*? '"')
                         ^
Protobuf3.g4:L533:     | ( '"' ( CHAR_VALUE)*? '"')
                               ^
Protobuf3.g4:L561:     : (DECIMALS DOT DECIMALS? EXPONENT? | DECIMALS EXPONENT | DOT DECIMALS EXPONENT?)
                         ^
Protobuf3.g4:L581:     : ([1-9]) DECIMAL_DIGIT*
                         ^
01/28-06:17:32 ~/issues/g4-3949/protobuf3

[teverett]

@kaby76 are changes needed, or is this ok to merge?

[kaby76]

@teverett This PR is NOT COMPLETE. The renaming of PROTO3_LIT_DOBULE to PROTO3_LIT_DOUBLE was done here:
https://github.com/maxwell2011/grammars-v4/blob/0036eaf4ac650e45c445c301cf326fbd316b9a08/protobuf3/Protobuf3.g4#L465

But, it was not renamed in these two places:
https://github.com/maxwell2011/grammars-v4/blob/0036eaf4ac650e45c445c301cf326fbd316b9a08/protobuf3/Protobuf3.g4#L27

https://github.com/maxwell2011/grammars-v4/blob/0036eaf4ac650e45c445c301cf326fbd316b9a08/protobuf3/Protobuf3.g4#L309

The Antlr tool outputs a warning "warning(125): Protobuf3.g4:27:37: implicit definition of token PROTO3_LIT_DOBULE in parser", but we don't quit on warnings. The grammar was changed, but it's not clear if there is input that tests this change.