Change 'equals' method calls to be null safe

src/com/owncloud/android/ui/activity/ShareActivity.java

@@ -133,7 +133,7 @@ public class ShareActivity extends FileActivity
     private int getAppropiatePermissions(ShareType shareType) {
 
         // check if the Share is FERERATED
-        boolean isFederated = shareType.equals(ShareType.FEDERATED);
+        boolean isFederated = ShareType.FEDERATED.equals(shareType);
 
         if (getFile().isSharedWithMe()) {
             return OCShare.READ_PERMISSION_FLAG;    // minimum permissions

src/com/owncloud/android/ui/fragment/EditShareFragment.java

@@ -147,7 +147,7 @@ public class EditShareFragment extends Fragment {
             setPermissionsListening(editShareView, false);
 
             int sharePermissions = mShare.getPermissions();
-            boolean isFederated = mShare.getShareType().equals(ShareType.FEDERATED);
+            boolean isFederated = ShareType.FEDERATED.equals(mShare.getShareType());
             CompoundButton compound;
 
             compound = (CompoundButton) editShareView.findViewById(R.id.canShareSwitch);