Reserve signal for java heap dumps.

We will put instrumentation in ART to write out Java heap memory
information on receipt of this signal.

Bug: 136210868
Test: Flash blueline-userdebug and boot

Change-Id: I63173a4051c46b8569faaf3064e1db1dbd0ea3fe
diff --git a/libc/include/android/legacy_signal_inlines.h b/libc/include/android/legacy_signal_inlines.h
index 5ca9813..d2c7677 100644
--- a/libc/include/android/legacy_signal_inlines.h
+++ b/libc/include/android/legacy_signal_inlines.h
@@ -52,7 +52,7 @@
 
 static __inline int __ndk_legacy___libc_current_sigrtmin() {
   if (__libc_current_sigrtmin) return __libc_current_sigrtmin();
-  return __SIGRTMIN + 6; /* Should match __libc_current_sigrtmin. */
+  return __SIGRTMIN + 7; /* Should match __libc_current_sigrtmin. */
 }
 
 #undef SIGRTMAX
diff --git a/libc/private/sigrtmin.h b/libc/private/sigrtmin.h
index d78d980..5de1a32 100644
--- a/libc/private/sigrtmin.h
+++ b/libc/private/sigrtmin.h
@@ -39,13 +39,14 @@
 //   33 (__SIGRTMIN + 1)        libbacktrace
 //   34 (__SIGRTMIN + 2)        libcore
 //   35 (__SIGRTMIN + 3)        debuggerd -b
-//   36 (__SIGRTMIN + 4)        heapprofd
+//   36 (__SIGRTMIN + 4)        heapprofd native dumps
 //   37 (__SIGRTMIN + 5)        coverage (libprofile-extras)
+//   38 (__SIGRTMIN + 6)        heapprofd ART managed heap dumps
 //
 // If you change this, also change __ndk_legacy___libc_current_sigrtmin
 // in <android/legacy_signal_inlines.h> to match.
 
-#define __SIGRT_RESERVED 6
+#define __SIGRT_RESERVED 7
 static inline __always_inline sigset64_t filter_reserved_signals(sigset64_t sigset, int how) {
   int (*block)(sigset64_t*, int);
   int (*unblock)(sigset64_t*, int);
@@ -72,5 +73,6 @@
   unblock(&sigset, __SIGRTMIN + 3);
   unblock(&sigset, __SIGRTMIN + 4);
   unblock(&sigset, __SIGRTMIN + 5);
+  unblock(&sigset, __SIGRTMIN + 6);
   return sigset;
 }