Remove unused blob header files

Changelog: changed

app/views/projects/artifacts/file.html.haml

@@ -12,8 +12,6 @@
       = render 'projects/blob/header_content', blob: blob
 
       .file-actions.d-none.d-sm-block
-        = render 'projects/blob/viewer_switcher', blob: blob
-
         .btn-group{ role: "group" }<
           = copy_blob_source_button(blob)
           = download_blob_button(blob)

app/views/projects/blob/_header.html.haml

@@ -4,7 +4,6 @@
   = render 'projects/blob/header_content', blob: blob
 
   .file-actions.gl-display-flex.gl-align-items-center.gl-flex-wrap.gl-md-justify-content-end<
-    = render 'projects/blob/viewer_switcher', blob: blob unless blame
     = render 'shared/web_ide_button', blob: blob
     .btn-group.gl-ml-3{ role: "group" }
       = copy_blob_source_button(blob) unless blame

app/views/projects/blob/_viewer_switcher.html.haml

-- if blob.show_viewer_switcher?
-  - simple_viewer = blob.simple_viewer
-  - rich_viewer = blob.rich_viewer
-
-  .btn-group.js-blob-viewer-switcher.gl-ml-3{ role: "group" }>
-    - simple_label = format(_("Display %{viewer_type}"), viewer_type: simple_viewer.switcher_title)
-    %button.btn.gl-button.btn-default.btn-icon.js-blob-viewer-switch-btn.has-tooltip{ 'aria-label' => simple_label, title: simple_label, data: { viewer: 'simple', container: 'body' } }>
-      = sprite_icon(simple_viewer.switcher_icon)
-
-    - rich_label = format(_("Display %{viewer_type}"), viewer_type: rich_viewer.switcher_title)
-    %button.btn.gl-button.btn-default.btn-icon.js-blob-viewer-switch-btn.has-tooltip{ 'aria-label' => rich_label, title: rich_label, data: { viewer: 'rich', container: 'body' } }>
-      = sprite_icon(rich_viewer.switcher_icon)

locale/gitlab.pot

@@ -17413,9 +17413,6 @@ msgstr[1] ""
 msgid "Display"
 msgstr ""
-msgid "Display %{viewer_type}"
-msgstr ""
-
 msgid "Display alerts from all configured monitoring tools."
 msgstr ""