[Gutter] Add add/get Gutter methods to TextEditor

spec/text-editor-spec.coffee

@@ -4242,3 +4242,14 @@ describe "TextEditor", ->
         editor.checkoutHeadRevision()
 
         waitsForPromise -> editor.checkoutHeadRevision()
+
+  describe 'gutters', ->
+    describe '::addGutter', ->
+      it 'can add a gutter', ->
+        expect(editor.getGutters().length).toBe 0
+        options =
+          name: 'test-gutter'
+          priority: 1
+        gutter = editor.addGutter options
+        expect(editor.getGutters().length).toBe 1
+        expect(editor.getGutters()[0]).toBe gutter

src/text-editor.coffee

@@ -12,6 +12,7 @@ Model = require './model'
 Selection = require './selection'
 TextMateScopeSelector = require('first-mate').ScopeSelector
 {Directory} = require "pathwatcher"
+GutterContainer = require './gutter-container'
 
 # Public: This class represents all essential editing state for a single
 # {TextBuffer}, including cursor and selection positions, folds, and soft wraps.
@@ -68,6 +69,7 @@ class TextEditor extends Model
   suppressSelectionMerging: false
   updateBatchDepth: 0
   selectionFlashDuration: 500
+  gutterContainer: null
 
   @delegatesMethods 'suggestedIndentForBufferRow', 'autoIndentBufferRow', 'autoIndentBufferRows',
     'autoDecreaseIndentForBufferRow', 'toggleLineCommentForBufferRow', 'toggleLineCommentsForBufferRows',
@@ -112,6 +114,8 @@ class TextEditor extends Model
       @emit 'scroll-left-changed', scrollLeft if includeDeprecatedAPIs
       @emitter.emit 'did-change-scroll-left', scrollLeft
 
+    @gutterContainer = new GutterContainer
+
     atom.workspace?.editorAdded(this) if registerEditor
 
   serializeParams: ->
@@ -181,6 +185,7 @@ class TextEditor extends Model
     @buffer.release()
     @displayBuffer.destroy()
     @languageMode.destroy()
+    @gutterContainer.destroy()
     @emitter.emit 'did-destroy'
 
   ###
@@ -499,6 +504,15 @@ class TextEditor extends Model
   onDidChangeLineNumberGutterVisible: (callback) ->
     @emitter.on 'did-change-line-number-gutter-visible', callback
 
+  # Public: Creates and returns a {Gutter}.
+  # See {GutterContainer::addGutter} for more details.
+  addGutter: (options) ->
+    @gutterContainer.addGutter options
+
+  # Public: Returns the {Array} of all gutters on this editor.
+  getGutters: ->
+    @gutterContainer.getGutters()
+
   # Set the number of characters that can be displayed horizontally in the
   # editor.
   #