long-term downloads resume

* recovery infrastructure
* bump serialVersionUID of DownloadMission
* misc cleanup in DownloadMission.java
* remove unused/redundant from strings.xml

app/src/main/java/us/shandian/giga/get/MissionRecoveryInfo.java

@@ -0,0 +1,79 @@
+package us.shandian.giga.get;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+import android.support.annotation.NonNull;
+
+import org.schabi.newpipe.extractor.MediaFormat;
+import org.schabi.newpipe.extractor.stream.AudioStream;
+import org.schabi.newpipe.extractor.stream.Stream;
+import org.schabi.newpipe.extractor.stream.SubtitlesStream;
+import org.schabi.newpipe.extractor.stream.VideoStream;
+
+import java.io.Serializable;
+
+public class MissionRecoveryInfo implements Serializable, Parcelable {
+    private static final long serialVersionUID = 0L;
+    //public static final String DIRECT_SOURCE = "direct-source://";
+
+    public MediaFormat format;
+    String desired;
+    boolean desired2;
+    int desiredBitrate;
+
+    transient int attempts = 0;
+
+    String validateCondition = null;
+
+    public MissionRecoveryInfo(@NonNull Stream stream) {
+        if (stream instanceof AudioStream) {
+            desiredBitrate = ((AudioStream) stream).average_bitrate;
+            desired2 = false;
+        } else if (stream instanceof VideoStream) {
+            desired = ((VideoStream) stream).getResolution();
+            desired2 = ((VideoStream) stream).isVideoOnly();
+        } else if (stream instanceof SubtitlesStream) {
+            desired = ((SubtitlesStream) stream).getLanguageTag();
+            desired2 = ((SubtitlesStream) stream).isAutoGenerated();
+        } else {
+            throw new RuntimeException("Unknown stream kind");
+        }
+
+        format = stream.getFormat();
+        if (format == null) throw new NullPointerException("Stream format cannot be null");
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel parcel, int flags) {
+        parcel.writeInt(this.format.ordinal());
+        parcel.writeString(this.desired);
+        parcel.writeInt(this.desired2 ? 0x01 : 0x00);
+        parcel.writeInt(this.desiredBitrate);
+        parcel.writeString(this.validateCondition);
+    }
+
+    private MissionRecoveryInfo(Parcel parcel) {
+        this.format = MediaFormat.values()[parcel.readInt()];
+        this.desired = parcel.readString();
+        this.desired2 = parcel.readInt() != 0x00;
+        this.desiredBitrate = parcel.readInt();
+        this.validateCondition = parcel.readString();
+    }
+
+    public static final Parcelable.Creator<MissionRecoveryInfo> CREATOR = new Parcelable.Creator<MissionRecoveryInfo>() {
+        @Override
+        public MissionRecoveryInfo createFromParcel(Parcel source) {
+            return new MissionRecoveryInfo(source);
+        }
+
+        @Override
+        public MissionRecoveryInfo[] newArray(int size) {
+            return new MissionRecoveryInfo[size];
+        }
+    };
+}