am 18760af8: Cherry-pick: [Android WebView] Null check syncOnNewPictureStateToNative

* commit '18760af8':
  Cherry-pick: [Android WebView] Null check syncOnNewPictureStateToNative

android_webview/java/src/org/chromium/android_webview/AwContents.java

@@ -816,6 +816,7 @@ public class AwContents {
     }
 
     private void syncOnNewPictureStateToNative() {
+        if (mNativeAwContents == 0) return;
         nativeEnableOnNewPicture(mNativeAwContents, mPictureListenerEnabled || mClearViewActive);
     }