Podlite 1.12: a build for Android 4.1 (Xperia J) with ExoPlayer, speed and skip silences

- One build per Android level, as in Tenda and Plexamp Lite: build/Podlite.apk (Android 2.2+, versionCode 1308) and
  build/Podlite-api16.apk (Android 4.1+, 1316), from shared src/ plus platform/api8 or platform/api16; build.sh now
  runs on the local toolchain (aapt2, dx or R8, signapk.py; the JKS key converted for the run).
- Android 4.1 build: ExoPlayer 2.18.7 behind an Engine interface, with playback speed (player header) and skipping
  silences (Settings), a 3-minute buffer and MediaPlayer as fallback for audio it can't decode; a notification and
  lock screen with the cover and buttons; Holo; a menu button on phones without a Menu key; metered networks for
  "download on Wi-Fi only".
- Both builds: tlskit's Http.abort fix (a finished response's pooled connection is no longer closed under a later
  request); the lock screen's and newer headsets' play/pause keys.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/com/miniabs/net/Http.java

@@ -451,19 +451,25 @@ public final class Http {
     // ------------------------------------------------------------------ body streams
 
     private static final class FixedStream extends InputStream {
-        private final Conn c; private long left; private final boolean keepAlive; private boolean closed;
+        private final Conn c; private long left; private final boolean keepAlive; private volatile boolean closed;
 
         FixedStream(Conn c, long len, boolean keepAlive) {
             this.c = c; this.left = len; this.keepAlive = keepAlive;
             if (len == 0) finish(true);
         }
 
-        private void finish(boolean complete) {
+        private synchronized void finish(boolean complete) {
             if (closed) return;
             closed = true;
             if (complete && keepAlive) release(c); else c.close();
         }
 
+        synchronized void abort() {
+            if (closed) return;   // done: the connection may already be back in the pool, serving someone else
+            closed = true;
+            try { c.socket.close(); } catch (Exception ignored) {}
+        }
+
         @Override public int read() throws IOException {
             byte[] one = new byte[1];
             int n = read(one, 0, 1);
@@ -490,16 +496,22 @@ public final class Http {
 
     private static final class ChunkedStream extends InputStream {
         private final Conn c; private final boolean keepAlive;
-        private long chunkLeft = 0; private boolean eof; private boolean closed;
+        private long chunkLeft = 0; private boolean eof; private volatile boolean closed;
 
         ChunkedStream(Conn c, boolean keepAlive) { this.c = c; this.keepAlive = keepAlive; }
 
-        private void finish(boolean complete) {
+        private synchronized void finish(boolean complete) {
             if (closed) return;
             closed = true;
             if (complete && keepAlive) release(c); else c.close();
         }
 
+        synchronized void abort() {
+            if (closed) return;   // done: the connection may already be back in the pool, serving someone else
+            closed = true;
+            try { c.socket.close(); } catch (Exception ignored) {}
+        }
+
         private boolean nextChunk() throws IOException {
             if (eof) return false;
             String line = readLine(c.in);
@@ -551,7 +563,7 @@ public final class Http {
     }
 
     private static final class EofStream extends InputStream {
-        private final Conn c; private boolean closed;
+        private final Conn c; private volatile boolean closed;
         EofStream(Conn c) { this.c = c; }
 
         @Override public int read() throws IOException {
@@ -568,21 +580,25 @@ public final class Http {
             return n;
         }
 
-        @Override public void close() {
+        @Override public synchronized void close() {
             if (!closed) { closed = true; c.close(); }
         }
-    }
 
-    /** Close one in-flight response's socket from another thread (used to abort streams). */
-    public static void abort(Response r) {
-        if (r == null) return;
-        InputStream b = r.body;
-        Conn c = null;
-        if (b instanceof FixedStream) c = ((FixedStream) b).c;
-        else if (b instanceof ChunkedStream) c = ((ChunkedStream) b).c;
-        else if (b instanceof EofStream) c = ((EofStream) b).c;
-        if (c != null) {
+        synchronized void abort() {
+            if (closed) return;
+            closed = true;
             try { c.socket.close(); } catch (Exception ignored) {}
         }
     }
+
+    /** Close one in-flight response's socket from another thread (used to abort streams). A response that has
+     *  already been read to the end is left alone: its connection went back to the pool and may be carrying
+     *  another request by now (closing it cut read-ahead downloads short: "Unexpected end of stream"). */
+    public static void abort(Response r) {
+        if (r == null) return;
+        InputStream b = r.body;
+        if (b instanceof FixedStream) ((FixedStream) b).abort();
+        else if (b instanceof ChunkedStream) ((ChunkedStream) b).abort();
+        else if (b instanceof EofStream) ((EofStream) b).abort();
+    }
 }