UploadFileOperation: ensure channel is closed

Triggers strict mode warnings

Signed-off-by: Álvaro Brey <alvaro.brey@nextcloud.com>

app/src/main/java/com/owncloud/android/operations/UploadFileOperation.java

@@ -738,6 +738,8 @@ public class UploadFileOperation extends SyncOperation {
         File originalFile = new File(mOriginalStoragePath);
         File expectedFile = null;
         FileLock fileLock = null;
+        FileChannel channel = null;
+
         long size;
 
         try {
@@ -768,7 +770,6 @@ public class UploadFileOperation extends SyncOperation {
 
             final Long creationTimestamp = FileUtil.getCreationTimestamp(originalFile);
 
-            FileChannel channel = null;
             try {
                 channel = new RandomAccessFile(mFile.getStoragePath(), "rw").getChannel();
                 fileLock = channel.tryLock();
@@ -859,6 +860,14 @@ public class UploadFileOperation extends SyncOperation {
                 }
             }
 
+            if (channel != null) {
+                try {
+                    channel.close();
+                } catch (IOException e) {
+                    Log_OC.w(TAG, "Failed to close file channel");
+                }
+            }
+
             if (temporalFile != null && !originalFile.equals(temporalFile)) {
                 temporalFile.delete();
             }