Tweak diagnostic wording for init list narrowing

The conventional form is '<action> to silence this warning'.

Also call the diagnostic an 'issue' rather than a 'message' because the latter
term is more widely used with reference to message expressions.

llvm-svn: 209052
diff --git a/clang/test/SemaCXX/microsoft-cxx0x.cpp b/clang/test/SemaCXX/microsoft-cxx0x.cpp
index 79bd7c3..58ab940 100644
--- a/clang/test/SemaCXX/microsoft-cxx0x.cpp
+++ b/clang/test/SemaCXX/microsoft-cxx0x.cpp
@@ -6,7 +6,7 @@
      unsigned int a;
 };
 int b = 3;
-A var = {  b }; // expected-warning {{ cannot be narrowed }} expected-note {{override}}
+A var = {  b }; // expected-warning {{ cannot be narrowed }} expected-note {{insert an explicit cast to silence this issue}}
 
 
 namespace PR13433 {