* Attempt to fix SDK / AWT panels issue "Framebuffer doesn’t have any renderbuffers attached."

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@9991 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

engine/src/lwjgl/com/jme3/system/lwjgl/LwjglOffscreenBuffer.java

@@ -104,14 +104,19 @@ public class LwjglOffscreenBuffer extends LwjglContext implements Runnable {
     }
 
     protected void runLoop(){
-        if (!created.get())
+        if (!created.get()) {
             throw new IllegalStateException();
+        }
 
         if (pbuffer.isBufferLost()) {
             pbuffer.destroy();
+
             try {
                 pbuffer = new Pbuffer(width, height, pixelFormat, null);
                 pbuffer.makeCurrent();
+                
+                // Context MUST be reset here to avoid invalid objects!
+                renderer.invalidateState();
             } catch (LWJGLException ex) {
                 listener.handleError("Failed to restore pbuffer content", ex);
             }