Make sure binder ioctl structs don't contain uninitialized values.

Change-Id: I8a678f91262417bb120e65e32c244ce1512b46c2
diff --git a/libs/binder/IPCThreadState.cpp b/libs/binder/IPCThreadState.cpp
index 95cfddf..392193b 100644
--- a/libs/binder/IPCThreadState.cpp
+++ b/libs/binder/IPCThreadState.cpp
@@ -851,6 +851,9 @@
     tr.target.handle = handle;
     tr.code = code;
     tr.flags = binderFlags;
+    tr.cookie = 0;
+    tr.sender_pid = 0;
+    tr.sender_euid = 0;
     
     const status_t err = data.errorCheck();
     if (err == NO_ERROR) {