[LyX/master] Partial fix for bug #11586

[Enrico Forestieri]

commit bda3b799c579a1b104bf605a5d5d380b9b5cc949
Author: Enrico Forestieri <for...@lyx.org>
Date:   Sun May 26 09:27:46 2019 +0200

    Partial fix for bug #11586
    
    Do not replace a latex command with the corresponding symbol
    in the unicodesymbols file unless it can be encoded in the
    document encoding.
---
 src/mathed/MathParser.cpp |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/src/mathed/MathParser.cpp b/src/mathed/MathParser.cpp
index 0fe6e0f..3449cff 100644
--- a/src/mathed/MathParser.cpp
+++ b/src/mathed/MathParser.cpp
@@ -2081,7 +2081,7 @@ bool Parser::parse1(InsetMathGrid & grid, unsigned flags,
                                                        Encodings::MATH_CMD | 
Encodings::TEXT_CMD,
                                                        is_combining, 
termination);
                                        }
-                                       if (c) {
+                                       if (c && 
buf->params().encoding().encodable(c)) {
                                                if (termination) {
                                                        if (nextToken().cat() 
== catBegin) {
                                                                getToken();