Fix compile error reaching end of non-void function

DESCRIPTION

@@ -8,7 +8,8 @@ Authors@R: c(
     person("Steffen", "Neumann", email="[email protected]", role=c("aut","cre")),
     person("Laurent", "Gatto", email="[email protected]", role=c("aut")),
     person("Qiakng", "Kou", email="[email protected]", role=c("aut")),
-    person("David","Rauh",email="[email protected]", role=c("ctb"))
+    person("David","Rauh",email="[email protected]", role=c("ctb")),
+    person("Sascha","Manier",email="[email protected]", role=c("ctb"))
     )
 Description: mzR provides a unified API to the common file formats and
         parsers available for mass spectrometry data. It comes with a

src/pwiz/data/msdata/MSData.cpp

@@ -1112,6 +1112,8 @@ PWIZ_API_DECL size_t SpectrumList::findAbbreviated(const string& abbreviatedId,
         if ((result >= 0 && result < size()) || s == 0)
             return result;
     }
+
+    return size();
 }