Revert "Revert "Revert "Revert "Add BacktraceOffline for offline backtracing.""""

This reverts commit 94ece83270deca76c69f5755f8c0ff5c859341fd.

Change-Id: Ie06465c89a5fc115517130f9f2904cc855973155
diff --git a/libbacktrace/Backtrace.cpp b/libbacktrace/Backtrace.cpp
index 97f0ef4..9ead452 100644
--- a/libbacktrace/Backtrace.cpp
+++ b/libbacktrace/Backtrace.cpp
@@ -30,6 +30,7 @@
 #include <cutils/threads.h>
 
 #include "BacktraceLog.h"
+#include "BacktraceOffline.h"
 #include "thread_utils.h"
 #include "UnwindCurrent.h"
 #include "UnwindPtrace.h"
@@ -140,3 +141,8 @@
     return new UnwindPtrace(pid, tid, map);
   }
 }
+
+Backtrace* Backtrace::CreateOffline(pid_t pid, pid_t tid, BacktraceMap* map,
+                                    const backtrace_stackinfo_t& stack, bool cache_file) {
+  return new BacktraceOffline(pid, tid, map, stack, cache_file);
+}