Move libmemunreachable into namespace android

Putting libmemunreachable in the global C++ namespace was an oversight,
move it into namespace android.

Test: m -j checkbuild
Change-Id: I0799906f6463178cb04a719bb4054cad33a50dbe
diff --git a/LeakPipe.h b/LeakPipe.h
index e6aee5f..94d4aa4 100644
--- a/LeakPipe.h
+++ b/LeakPipe.h
@@ -26,6 +26,8 @@
 #include "ScopedPipe.h"
 #include "log.h"
 
+namespace android {
+
 // LeakPipe implements a pipe that can transfer vectors of simple objects
 // between processes.  The pipe is created in the sending process and
 // transferred over a socketpair that was created before forking.  This ensures
@@ -187,4 +189,6 @@
   int sv_[2];
 };
 
+}  // namespace android
+
 #endif  // LIBMEMUNREACHABLE_LEAK_PIPE_H_