[Gutter][DOM Persistence] Add ::hideNode and ::showNode to GutterComponent classes

src/custom-gutter-component.coffee

@@ -14,6 +14,7 @@ class CustomGutterComponent
   constructor: ({@gutter}) ->
     @decorationNodesById = {}
     @decorationItemsById = {}
+    @visible = true
 
     @domNode = atom.views.getView(@gutter)
     @decorationsNode = @domNode.firstChild
@@ -26,6 +27,16 @@ class CustomGutterComponent
   getName: ->
     @gutter.name
 
+  hideNode: ->
+    if @visible
+      @domNode.style.display = 'none'
+      @visible = false
+
+  showNode: ->
+    if !@visible
+      @domNode.style.removeProperty('display')
+      @visible = true
+
   updateSync: (state) ->
     gutterProps = state.lineNumberGutter
     decorationState = state.gutters.customDecorations[@getName()]

src/line-number-gutter-component.coffee

@@ -9,6 +9,7 @@ class LineNumberGutterComponent
 
   constructor: ({@onMouseDown, @editor, @gutter}) ->
     @lineNumberNodesById = {}
+    @visible = true
 
     @domNode = atom.views.getView(@gutter)
     @lineNumbersNode = @domNode.firstChild
@@ -22,6 +23,16 @@ class LineNumberGutterComponent
   getName: ->
     @gutter.name
 
+  hideNode: ->
+    if @visible
+      @domNode.style.display = 'none'
+      @visible = false
+
+  showNode: ->
+    if !@visible
+      @domNode.style.removeProperty('display')
+      @visible = true
+
   updateSync: (state) ->
     @newState = state.lineNumberGutter
     @oldState ?= {lineNumbers: {}}