Add BacktraceOffline for offline backtracing.

It is used by simpeleprf for stack unwinding.

Bug: 22229391
Change-Id: I26d698610ccdc9545da837bc5a8a9ec787f27a6b
diff --git a/include/backtrace/BacktraceMap.h b/include/backtrace/BacktraceMap.h
index bb18aa2..2373c45 100644
--- a/include/backtrace/BacktraceMap.h
+++ b/include/backtrace/BacktraceMap.h
@@ -31,6 +31,7 @@
 
 #include <deque>
 #include <string>
+#include <vector>
 
 struct backtrace_map_t {
   uintptr_t start = 0;
@@ -48,6 +49,8 @@
   // is unsupported.
   static BacktraceMap* Create(pid_t pid, bool uncached = false);
 
+  static BacktraceMap* Create(pid_t pid, const std::vector<backtrace_map_t>& maps);
+
   virtual ~BacktraceMap();
 
   // Fill in the map data structure for the given address.