Set default request id to invalid one

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryDetailScene.java

@@ -103,6 +103,7 @@ import com.hippo.widget.ProgressView;
 import com.hippo.widget.SimpleGridAutoSpanLayout;
 import com.hippo.yorozuya.FileUtils;
 import com.hippo.yorozuya.IOUtils;
+import com.hippo.yorozuya.IntIdGenerator;
 import com.hippo.yorozuya.SimpleHandler;
 import com.hippo.yorozuya.ViewUtils;
 
@@ -250,7 +251,7 @@ public class GalleryDetailScene extends BaseScene implements View.OnClickListene
 
     @Nullable
     private GalleryDetail mGalleryDetail;
-    private int mRequestId;
+    private int mRequestId = IntIdGenerator.INVALID_ID;
 
     private Pair<String, String>[] mTorrentList;
 

app/src/main/java/com/hippo/ehviewer/ui/scene/SignInScene.java

@@ -42,6 +42,7 @@ import com.hippo.ehviewer.client.parser.ProfileParser;
 import com.hippo.ehviewer.ui.MainActivity;
 import com.hippo.scene.Announcer;
 import com.hippo.scene.SceneFragment;
+import com.hippo.yorozuya.IntIdGenerator;
 import com.hippo.yorozuya.ViewUtils;
 
 import junit.framework.Assert;
@@ -79,7 +80,7 @@ public final class SignInScene extends SolidScene implements EditText.OnEditorAc
     private TextView mSkipSigningIn;
 
     private boolean mSigningIn;
-    private int mRequestId;
+    private int mRequestId = IntIdGenerator.INVALID_ID;
 
     @Override
     public boolean needShowLeftDrawer() {