Disable fdtrack post-fork.

Also delete some fdsan code that attempts to check for the post-fork
state, but never will, because we update the cached pid upon fork.

Bug: http://b/174542867
Test: /data/nativetest64/bionic-unit-tests/bionic-unit-tests
Test: treehugger
Change-Id: I9b748dac9de9b4c741897d93e64d31737e52bf8e
diff --git a/libc/bionic/fork.cpp b/libc/bionic/fork.cpp
index 8c5cf2b..d432c6d 100644
--- a/libc/bionic/fork.cpp
+++ b/libc/bionic/fork.cpp
@@ -31,6 +31,7 @@
 #include <android/fdsan.h>
 
 #include "private/bionic_defs.h"
+#include "private/bionic_fdtrack.h"
 #include "pthread_internal.h"
 
 __BIONIC_WEAK_FOR_NATIVE_BRIDGE_INLINE
@@ -55,9 +56,10 @@
   int result = __clone_for_fork();
 
   if (result == 0) {
-    // Disable fdsan post-fork, so we don't falsely trigger on processes that
+    // Disable fdsan and fdtrack post-fork, so we don't falsely trigger on processes that
     // fork, close all of their fds, and then exec.
     android_fdsan_set_error_level(ANDROID_FDSAN_ERROR_LEVEL_DISABLED);
+    android_fdtrack_set_globally_enabled(false);
 
     // Reset the stack_and_tls VMA name so it doesn't end with a tid from the
     // parent process.