Add the TID to the CallStack.

src/processor/call_stack.cc

 // Copyright (c) 2006, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
@@ skipping 30 matching lines @@
 CallStack::~CallStack() {
   Clear();
 }
 
 void CallStack::Clear() {
   for (vector<StackFrame *>::const_iterator iterator = frames_.begin();
        iterator != frames_.end();
        ++iterator) {
     delete *iterator;
   }
+  tid_ = 0;
 }
 
 }  // namespace google_breakpad