bluetooth: Post a task when sending GATT events to simulate another thread.

device/bluetooth/test/bluetooth_test_android.h

Index: device/bluetooth/test/bluetooth_test_android.h
diff --git a/device/bluetooth/test/bluetooth_test_android.h b/device/bluetooth/test/bluetooth_test_android.h
index 4203b0852091b0362ad96980a0302557d5ce1bba..4268f271af2e1d1f6a5e7b9ea76523305469b99c 100644
--- a/device/bluetooth/test/bluetooth_test_android.h
+++ b/device/bluetooth/test/bluetooth_test_android.h
@@ -161,6 +161,11 @@ class BluetoothTestAndroid : public BluetoothTestBase {
       const base::android::JavaParamRef<jobject>& caller,
       const bool powered);
 
+  // Posts a task to be run on the current message loop.
+  void PostTaskFromJava(JNIEnv* env,
+                        const base::android::JavaParamRef<jobject>& caller,
+                        const base::android::JavaParamRef<jobject>& runnable);
+
   base::android::ScopedJavaGlobalRef<jobject> j_fake_bluetooth_adapter_;
 
   int gatt_open_connections_ = 0;