[rider]: allow to change initial icon area width

platform/diff-impl/src/com/intellij/diff/util/DiffUtil.java

@@ -214,6 +214,7 @@ public class DiffUtil {
     editor.getSettings().setShowIntentionBulb(false);
     ((EditorMarkupModel)editor.getMarkupModel()).setErrorStripeVisible(true);
     editor.getGutterComponentEx().setShowDefaultGutterPopup(false);
+    editor.getGutterComponentEx().resetInitialIconAreaWidth();
 
     if (enableFolding) {
       setFoldingModelSupport(editor);

platform/platform-impl/src/com/intellij/execution/impl/ConsoleViewUtil.java

@@ -83,6 +83,7 @@ public class ConsoleViewUtil {
       editorSettings.setRightMarginShown(false);
       editorSettings.setCaretRowShown(false);
       editor.getGutterComponentEx().setPaintBackground(false);
+      editor.getGutterComponentEx().resetInitialIconAreaWidth();
 
       editor.putUserData(EDITOR_IS_CONSOLE_VIEW, true);
 

platform/platform-impl/src/com/intellij/openapi/diff/impl/DiffUtil.java

@@ -93,6 +93,7 @@ public class DiffUtil {
     EditorEx editor = (EditorEx)(isViewer ? factory.createViewer(document, project) : factory.createEditor(document, project));
     editor.putUserData(DiffManagerImpl.EDITOR_IS_DIFF_KEY, Boolean.TRUE);
     editor.getGutterComponentEx().revalidateMarkup();
+    editor.getGutterComponentEx().resetInitialIconAreaWidth();
 
     if (fileType != null && project != null && !project.isDisposed()) {
       CodeStyleFacade codeStyleFacade = CodeStyleFacade.getInstance(project);

platform/platform-impl/src/com/intellij/openapi/editor/ex/EditorGutterComponentEx.java

@@ -62,4 +62,8 @@ public abstract class EditorGutterComponentEx extends JComponent implements Edit
   public abstract void setForceShowLeftFreePaintersArea(boolean value);
 
   public abstract void setForceShowRightFreePaintersArea(boolean value);
+
+  public abstract void setInitialIconAreaWidth(int width);
+
+  public abstract void resetInitialIconAreaWidth();
 }

platform/platform-impl/src/com/intellij/openapi/editor/impl/EditorGutterComponentImpl.java

@@ -127,6 +127,7 @@ class EditorGutterComponentImpl extends EditorGutterComponentEx implements Mouse
   private final EditorImpl myEditor;
   private final FoldingAnchorsOverlayStrategy myAnchorsDisplayStrategy;
   @Nullable private TIntObjectHashMap<List<GutterMark>> myLineToGutterRenderers;
+  private int myStartIconAreaWidth = START_ICON_AREA_WIDTH;
   private int myIconsAreaWidth;
   private int myLineNumberAreaWidth;
   private int myAdditionalLineNumberAreaWidth;
@@ -809,7 +810,7 @@ class EditorGutterComponentImpl extends EditorGutterComponentEx implements Mouse
       }
     });
 
-    int minWidth = areIconsShown() ? scaleWidth(START_ICON_AREA_WIDTH) : 0;
+    int minWidth = areIconsShown() ? scaleWidth(myStartIconAreaWidth) : 0;
     myIconsAreaWidth = canShrink ? minWidth : Math.max(myIconsAreaWidth, minWidth);
 
     processGutterRenderers((line, renderers) -> {
@@ -1804,6 +1805,16 @@ class EditorGutterComponentImpl extends EditorGutterComponentEx implements Mouse
     myForceRightFreePaintersAreaShown = value;
   }
 
+  @Override
+  public void setInitialIconAreaWidth(int width) {
+    myStartIconAreaWidth = width;
+  }
+
+  @Override
+  public void resetInitialIconAreaWidth() {
+    myStartIconAreaWidth = START_ICON_AREA_WIDTH;
+  }
+
   private void invokePopup(MouseEvent e) {
     final ActionManager actionManager = ActionManager.getInstance();
     if (myEditor.getMouseEventArea(e) == EditorMouseEventArea.ANNOTATIONS_AREA) {