Missing error information for invalid input

[trevorgithub]

I apologize if this is a duplicate. I did skim the issues, but didn't notice the same thing (unless I misunderstood an existing issue, which is entirely possible).

I have a grammar that parsed correctly with invalid input in 4.5.1 & 4.6, but doesn't report errors in 4.7.

Here's the grammar, which I named Sample.g4 (sorry about the formatting; I used insert code but it didn't format as expected):

`grammar Sample;

fragment TERM_CHAR
: ~(' ' | '\t' | '\n' | '\r' | '\u3000'
| '"' | '\u201c' | '\u201d' | '(' | ')' | '\')
;

LPAREN : '(' ;
RPAREN : ')' ;

AND : 'AND' ;
OR : 'OR' ;

TERM_CONTENT : (TERM_CHAR)+ ;

WS
: ( ' '
| '\t'
| '\r'
| '\n'
| '\u3000'
)
-> channel(HIDDEN)
;

expression : noneExpression;
noneExpression : (orExpression)+;
orExpression : andExpression (OR andExpression);
andExpression : atom (AND atom);

atom : (term
| parent)
;

term : TERM_CONTENT | '\' ;

parent : LPAREN noneExpression? RPAREN ;`

Steps to reproduce:

Preconditions:

1. Install & configure ANTLR 4.7
2. Navigate to folder with Sample.g4, then follow the next steps

Steps to follow in shell, within folder containing Sample.g4:

1. antlr4 Sample.g4
2. javac *.java
3. grun Sample expression -gui
   a) Enter this string as standard input:
   xxx ) yyy (zzz OR hhh)
   ^D

Expected results:
(This is the behaviour seen using ANTLR 4.6)
The tree should show several nodes, with multiple branches & highlight an error node (the right parenthesis)
Errors should be written to the console:
line 1:4 extraneous input ')' expecting {, '', '(', 'AND', 'OR', TERM_CONTENT}

Actual results:

The tree shows a single branch, with no error nodes highlighted
No error are written to the console