Do not assert on POSIXDYLD double-eAdd.

[sas]

Summary

This has been discovered while experimenting with the gecko linker on android.
In general, assert()'ing on "user input" is a bad idea.

[clayborg]

lgtm

lldb/trunk/source/Plugins/DynamicLoader/POSIX-DYLD/DYLDRendezvous.cpp

DYLDRendezvous::UpdateSOEntries()
     // loaded modules.
     if (m_previous.state == eConsistent && m_current.state == eConsistent) 
         return TakeSnapshot(m_soentries);
 
     // If we are about to add or remove a shared object clear out the current
     // state and take a snapshot of the currently loaded images.
     if (m_current.state == eAdd || m_current.state == eDelete)
     {
-        assert(m_previous.state == eConsistent || (m_previous.state == eAdd && m_current.state == eDelete));
+        // Some versions of the android dynamic linker might send two
+        // notifications with state == eAdd back to back. Ignore them
+        // until we get an eConsistent notification.
+        if (!(m_previous.state == eConsistent || (m_previous.state == eAdd && m_current.state == eDelete)))
+            return false;
+
         m_soentries.clear();
         m_added_soentries.clear();
         m_removed_soentries.clear();
         return TakeSnapshot(m_soentries);
     }
     assert(m_current.state == eConsistent);
 
     // Otherwise check the previous state to determine what to expect and update