fix(uploads): Don't allow dragging of uploading images (Fixes #366)

internal_packages/composer/lib/image-file-upload.cjsx

@@ -1,7 +1,7 @@
 path = require 'path'
 React = require 'react'
 FileUpload = require './file-upload'
-{RetinaImg, DraggableImg} = require 'nylas-component-kit'
+{RetinaImg} = require 'nylas-component-kit'
 
 class ImageFileUpload extends FileUpload
   @displayName: 'ImageFileUpload'
@@ -12,7 +12,7 @@ class ImageFileUpload extends FileUpload
   render: =>
     <div className="file-wrap file-image-wrap file-upload">
       <div className="file-action-icon" onClick={@_onClickRemove}>
-        <RetinaImg name="image-cancel-button.png"/>
+        <RetinaImg name="image-cancel-button.png" mode={RetinaImg.Mode.ContentPreserve}/>
       </div>
 
       <div className="file-preview">
@@ -20,7 +20,7 @@ class ImageFileUpload extends FileUpload
           <div className="file-name">{@props.uploadData.fileName}</div>
         </div>
 
-        <DraggableImg src={@props.uploadData.filePath} />
+        <img src={@props.uploadData.filePath} onDragStart={@_onDragStart}/>
       </div>
 
       <div className={"progress-bar-wrap state-#{@props.uploadData.state}"}>
@@ -28,4 +28,7 @@ class ImageFileUpload extends FileUpload
       </div>
     </div>
 
+  _onDragStart: (event) ->
+    event.preventDefault()
+
 module.exports = ImageFileUpload