Fix NullPointerException when connected but no video frame decoded

remoting/android/java/src/org/chromium/chromoting/DesktopView.java

Index: remoting/android/java/src/org/chromium/chromoting/DesktopView.java
diff --git a/remoting/android/java/src/org/chromium/chromoting/DesktopView.java b/remoting/android/java/src/org/chromium/chromoting/DesktopView.java
index 26cf83a6e5bc4b5f7b537f2e9e06ba8eb4231a3b..e9ed440034f973c9159482d8283b8ebbb9fdac2e 100644
--- a/remoting/android/java/src/org/chromium/chromoting/DesktopView.java
+++ b/remoting/android/java/src/org/chromium/chromoting/DesktopView.java
@@ -83,6 +83,11 @@ public class DesktopView extends SurfaceView implements DesktopViewInterface, Ru
         }
 
         Bitmap image = JniInterface.getVideoFrame();
+        if (image == null) {
+            // This can happen if the client is connected, but a complete video frame has not yet
+            // been decoded.
+            return;
+        }
 
         int width = image.getWidth();
         int height = image.getHeight();