[Support] Introduce createStringError helper function

The function in question is copy-pasted lots of times in DWARF-related classes.
Thus it will make sense to place its implementation into the Support library.

Reviewed by: lhames

Differential Revision: https://reviews.llvm.org/D49824



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@337995 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Support/Error.cpp

@@ -112,6 +112,10 @@ std::error_code StringError::convertToErrorCode() const {
   return EC;
 }
 
+Error createStringError(std::error_code EC, char const *Msg) {
+  return make_error<StringError>(Msg, EC);
+}
+
 void report_fatal_error(Error Err, bool GenCrashDiag) {
   assert(Err && "report_fatal_error called with success value");
   std::string ErrMsg;