Fix problem with wait_for_gdb.

When someone enables wait_for_gdb, activity manager will kill the
stopped process before a developer can attach to the process. To
allow debugging in this case, change the code to only contact the
activity manager right before continuing the process that is
crashing.

Also, modify the conditions under which to do a gdb attach. The previous
code did a partial attach if perform_dump failed. The new version simply
allows an attach regardless of whether perform_dump passes or fails.

Bug: 28409358
Change-Id: I4fe8d390c212d47e007cbe6543c2d114c3c7aeff
diff --git a/debuggerd/tombstone.h b/debuggerd/tombstone.h
index 7f3eebe..487d950 100644
--- a/debuggerd/tombstone.h
+++ b/debuggerd/tombstone.h
@@ -34,6 +34,6 @@
 /* Creates a tombstone file and writes the crash dump to it. */
 void engrave_tombstone(int tombstone_fd, BacktraceMap* map, pid_t pid, pid_t tid,
                        const std::set<pid_t>& siblings, int signal, int original_si_code,
-                       uintptr_t abort_msg_address, int amfd);
+                       uintptr_t abort_msg_address, std::string* amfd_data);
 
 #endif // _DEBUGGERD_TOMBSTONE_H