datamodel: use equals for string comparison.

It is almost always a mistake to compare two instances of java.lang.String using reference equality == or !=, because it is not comparing actual value but locations in memory.

Signed-off-by: ardevd <edvard.holst@gmail.com>

src/main/java/com/owncloud/android/datamodel/FileDataStorageManager.java

@@ -1471,7 +1471,7 @@ public class FileDataStorageManager {
         // Reset flags & Remove shares for this files
         String filePath = "";
         for (OCShare share : shares) {
-            if (filePath != share.getPath()) {
+            if (filePath.equals(share.getPath())) {
                 filePath = share.getPath();
                 resetShareFlagInAFile(filePath);
                 operations = prepareRemoveSharesInFile(filePath, operations);