Correctly set the thread priority for ConnectionThreads.

This does not change the actual thread priority but if the default priority
changes, this will have the desired result of being slightly less favorable.

I tried messing with the priorities to see if a higher or lower priority helped
but it seemed to do more harm than good. It might be worth more investigation to
find out where all the thread time is being spent so we can determine the
correct priority.

core/java/android/net/http/ConnectionThread.java

@@ -69,6 +69,7 @@ class ConnectionThread extends Thread {
      */
     public void run() {
         android.os.Process.setThreadPriority(
+                android.os.Process.THREAD_PRIORITY_DEFAULT +
                 android.os.Process.THREAD_PRIORITY_LESS_FAVORABLE);
 
         // these are used to get performance data. When it is not in the timing,