CFI: Enable stack traces in renderer process in non-official CFI builds.

content/common/sandbox_linux/sandbox_linux.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <dirent.h>
 #include <fcntl.h>
 #include <sys/resource.h>
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <sys/types.h>
@@ skipping 122 matching lines @@
 void LinuxSandbox::PreinitializeSandbox() {
   CHECK(!pre_initialized_);
   seccomp_bpf_supported_ = false;
 #if defined(ANY_OF_AMTLU_SANITIZER)
   // Sanitizers need to open some resources before the sandbox is enabled.
   // This should not fork, not launch threads, not open a directory.
   __sanitizer_sandbox_on_notify(sanitizer_args());
   sanitizer_args_.reset();
 #endif
 
-#if !defined(NDEBUG)
+#if !defined(NDEBUG) || (defined(CFI_ENFORCEMENT) && !defined(OFFICIAL_BUILD))
   // The in-process stack dumping needs to open /proc/self/maps and cache
   // its contents before the sandbox is enabled.  It also pre-opens the
   // object files that are already loaded in the process address space.
   base::debug::EnableInProcessStackDumpingForSandbox();
 #endif  // !defined(NDEBUG)
 
   // Open proc_fd_. It would break the security of the setuid sandbox if it was
   // not closed.
   // If LinuxSandbox::PreinitializeSandbox() runs, InitializeSandbox() must run
   // as well.
@@ skipping 300 matching lines @@
 
 void LinuxSandbox::StopThreadAndEnsureNotCounted(base::Thread* thread) const {
   DCHECK(thread);
   base::ScopedFD proc_fd(OpenProc(proc_fd_));
   PCHECK(proc_fd.is_valid());
   CHECK(
       sandbox::ThreadHelpers::StopThreadAndWatchProcFS(proc_fd.get(), thread));
 }
 
 }  // namespace content