Fixed bug 2258 - Crash when using Android clipboard

chw

The Android clipboard manager methods must be called from the UI thread,
otherwise crashes of the dalvikvm happen.

android-project/src/org/libsdl/app/SDLActivity.java

@@ -277,6 +277,34 @@ public class SDLActivity extends Activity {
         return mSingleton;
     }
 
+    /**
+     * @return result of getSystemService(name) but executed on UI thread.
+     */
+    public Object getSystemServiceFromUiThread(final String name) {
+        final Object lock = new Object();
+        final Object[] results = new Object[2]; // array for writable variables
+        synchronized (lock) {
+            runOnUiThread(new Runnable() {
+                @Override
+                public void run() {
+                    synchronized (lock) {
+                        results[0] = getSystemService(name);
+                        results[1] = Boolean.TRUE;
+                        lock.notify();
+                    }
+                }
+            });
+            if (results[1] == null) {
+                try {
+                    lock.wait();
+                } catch (InterruptedException ex) {
+                    ex.printStackTrace();
+                }
+            }
+        }
+        return results[0];
+    }
+
     static class ShowTextInputTask implements Runnable {
         /*
          * This is used to regulate the pan&scan method to have some offset from