[analyzer][NFC] CallDescription should own the qualified name parts

Previously, CallDescription simply referred to the qualified name parts
by `const char*` pointers.
In the future we might want to dynamically load and populate
`CallDescriptionMaps`, hence we will need the `CallDescriptions` to
actually **own** their qualified name parts.

Reviewed By: martong, xazax.hun

Differential Revision: https://reviews.llvm.org/D113593

clang/include/clang/StaticAnalyzer/Core/PathSensitive/CallDescription.h

@@ -43,7 +43,7 @@ class CallDescription {
   mutable Optional<const IdentifierInfo *> II;
   // The list of the qualified names used to identify the specified CallEvent,
   // e.g. "{a, b}" represent the qualified names, like "a::b".
-  std::vector<const char *> QualifiedName;
+  std::vector<std::string> QualifiedName;
   Optional<unsigned> RequiredArgs;
   Optional<size_t> RequiredParams;
   int Flags;

clang/lib/StaticAnalyzer/Core/CallDescription.cpp

@@ -17,6 +17,7 @@
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Optional.h"
+#include <iterator>
 
 using namespace llvm;
 using namespace clang;
@@ -35,10 +36,12 @@ ento::CallDescription::CallDescription(
     int Flags, ArrayRef<const char *> QualifiedName,
     Optional<unsigned> RequiredArgs /*= None*/,
     Optional<size_t> RequiredParams /*= None*/)
-    : QualifiedName(QualifiedName), RequiredArgs(RequiredArgs),
+    : RequiredArgs(RequiredArgs),
       RequiredParams(readRequiredParams(RequiredArgs, RequiredParams)),
       Flags(Flags) {
   assert(!QualifiedName.empty());
+  this->QualifiedName.reserve(QualifiedName.size());
+  llvm::copy(QualifiedName, std::back_inserter(this->QualifiedName));
 }
 
 /// Construct a CallDescription with default flags.