Bugfix: GUI: Disable editing of sending addresses

This has been broken since 0.17 and nobody noticed, so just remove it entirely.

Bug 1 (since 0.17, bitcoin#10244): Instead of moving the label, the new address's label was set to the new address itself, and the actual label was lost completely.

Bug 2 (since 0.19, bitcoin#13756): "used" DestData should have been retained at the old address rather than deleted entirely.

Bug 3: Editing both the label and address in the label-editing dialog would still delete the label for the old address.

This commit just turns off the GUI editing capabilities, which should be the minimal needed to disable the functionality and therefore the bugs.

src/qt/addresstablemodel.cpp

@@ -307,9 +307,7 @@ Qt::ItemFlags AddressTableModel::flags(const QModelIndex &index) const
     Qt::ItemFlags retval = Qt::ItemIsSelectable | Qt::ItemIsEnabled;
     // Can edit address and label for sending addresses,
     // and only label for receiving addresses.
-    if(rec->type == AddressTableEntry::Sending ||
-      (rec->type == AddressTableEntry::Receiving && index.column()==Label))
-    {
+    if ((rec->type == AddressTableEntry::Sending || rec->type == AddressTableEntry::Receiving) && index.column() == Label) {
         retval |= Qt::ItemIsEditable;
     }
     return retval;

src/qt/editaddressdialog.cpp

@@ -34,6 +34,7 @@ EditAddressDialog::EditAddressDialog(Mode _mode, QWidget *parent) :
         break;
     case EditSendingAddress:
         setWindowTitle(tr("Edit sending address"));
+        ui->addressEdit->setEnabled(false);
         break;
     }
 

src/qt/forms/addressbookpage.ui

@@ -34,7 +34,7 @@
       <enum>Qt::CustomContextMenu</enum>
      </property>
      <property name="toolTip">
-      <string>Right-click to edit address or label</string>
+      <string>Right-click to edit label</string>
      </property>
      <property name="tabKeyNavigation">
       <bool>false</bool>