IDEA-153759 diff: remember "Disable editing" toggle state

platform/diff-impl/src/com/intellij/diff/tools/fragmented/UnifiedDiffViewer.java

@@ -1076,7 +1076,7 @@ public class UnifiedDiffViewer extends ListenerDiffViewerBase {
   private class MyReadOnlyLockAction extends TextDiffViewerUtil.ReadOnlyLockAction {
     public MyReadOnlyLockAction() {
       super(getContext());
-      init();
+      applyDefaults();
     }
 
     @Override

platform/diff-impl/src/com/intellij/diff/tools/util/base/TextDiffSettingsHolder.java

@@ -58,6 +58,7 @@ public class TextDiffSettingsHolder implements PersistentStateComponent<TextDiff
     public boolean SHOW_INDENT_LINES = false;
     public boolean USE_SOFT_WRAPS = false;
     public HighlightingLevel HIGHLIGHTING_LEVEL = HighlightingLevel.INSPECTIONS;
+    public boolean READ_ONLY_LOCK = true;
 
     // Fragments settings
     public boolean EXPAND_BY_DEFAULT = true;
@@ -165,6 +166,14 @@ public class TextDiffSettingsHolder implements PersistentStateComponent<TextDiff
       PLACE_SETTINGS.EXPAND_BY_DEFAULT = value;
     }
 
+    public boolean isReadOnlyLock() {
+      return PLACE_SETTINGS.READ_ONLY_LOCK;
+    }
+
+    public void setReadOnlyLock(boolean state) {
+      PLACE_SETTINGS.READ_ONLY_LOCK = state;
+    }
+
     //
     // Impl
     //

platform/diff-impl/src/com/intellij/diff/tools/util/base/TextDiffViewerUtil.java

@@ -36,7 +36,6 @@ import com.intellij.openapi.editor.event.EditorMouseEvent;
 import com.intellij.openapi.editor.ex.EditorEx;
 import com.intellij.openapi.project.DumbAware;
 import com.intellij.openapi.util.Condition;
-import com.intellij.openapi.util.Key;
 import com.intellij.ui.ToggleActionButton;
 import com.intellij.util.EditorPopupHandler;
 import com.intellij.util.Function;
@@ -52,7 +51,6 @@ import java.util.List;
 
 public class TextDiffViewerUtil {
   public static final Logger LOG = Logger.getInstance(TextDiffViewerUtil.class);
-  public static final Key<Boolean> READ_ONLY_LOCK_KEY = Key.create("ReadOnlyLockAction");
 
   @NotNull
   public static List<AnAction> createEditorPopupActions() {
@@ -341,14 +339,16 @@ public class TextDiffViewerUtil {
 
   public static abstract class ReadOnlyLockAction extends ToggleAction implements DumbAware {
     @NotNull protected final DiffContext myContext;
+    @NotNull protected final TextDiffSettings mySettings;
 
     public ReadOnlyLockAction(@NotNull DiffContext context) {
       super("Disable editing", null, AllIcons.Nodes.Padlock);
       myContext = context;
+      mySettings = getTextSettings(context);
       setEnabledInModalContext(true);
     }
 
-    protected void init() {
+    protected void applyDefaults() {
       if (isVisible()) { // apply default state
         setSelected(null, isSelected(null));
       }
@@ -366,12 +366,12 @@ public class TextDiffViewerUtil {
 
     @Override
     public boolean isSelected(AnActionEvent e) {
-      return myContext.getUserData(READ_ONLY_LOCK_KEY) != Boolean.FALSE;
+      return mySettings.isReadOnlyLock();
     }
 
     @Override
     public void setSelected(AnActionEvent e, boolean state) {
-      myContext.putUserData(READ_ONLY_LOCK_KEY, state);
+      mySettings.setReadOnlyLock(state);
       doApply(state);
     }
 
@@ -390,7 +390,7 @@ public class TextDiffViewerUtil {
     public EditorReadOnlyLockAction(@NotNull DiffContext context, @NotNull List<? extends EditorEx> editableEditors) {
       super(context);
       myEditableEditors = editableEditors;
-      init();
+      applyDefaults();
     }
 
     @Override