[analyzer] Add test for a crash fixed in r338775.

Do not crash if a CXXRecordDecl cannot be obtained for an object.

Special thanks for the reproduction to Alexander Kornienko.

llvm-svn: 338918
diff --git a/clang/lib/StaticAnalyzer/Checkers/InnerPointerChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/InnerPointerChecker.cpp
index b253e67..3a8964b 100644
--- a/clang/lib/StaticAnalyzer/Checkers/InnerPointerChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/InnerPointerChecker.cpp
@@ -133,10 +133,7 @@
     return false;
 
   CXXRecordDecl *Decl = ObjTy->getAsCXXRecordDecl();
-  if (!Decl || Decl->getName() != "basic_string")
-    return false;
-
-  return true;
+  return Decl && Decl->getName() == "basic_string";
 }
 
 bool InnerPointerChecker::isInvalidatingMemberFunction(