[clang] [analyzer] Modernize, improve and promote chroot checker (PR #117791)

[Balazs Benics via cfe-commits]

================
@@ -121,17 +183,40 @@ void ChrootChecker::checkPreCall(const CallEvent &Call,
     return;
 
   // If jail state is ROOT_CHANGED, generate BugReport.
-  void *const* k = C.getState()->FindGDM(ChrootChecker::getTag());
-  if (k)
-    if (isRootChanged((intptr_t) *k))
-      if (ExplodedNode *N = C.generateNonFatalErrorNode()) {
-        constexpr llvm::StringLiteral Msg =
-            "No call of chdir(\"/\") immediately after chroot";
-        C.emitReport(
-            std::make_unique<PathSensitiveBugReport>(BT_BreakJail, Msg, N));
-      }
+  const ChrootKind k = C.getState()->get<ChrootState>();
+  if (k == ROOT_CHANGED) {
----------------
steakhal wrote:

AFAICS we only do anything if this condition is met. I'd prefer an early return instead to reduce the indentation for the rest of the code.

https://github.com/llvm/llvm-project/pull/117791