Use rails helper image-url for reference images in css

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

app/assets/stylesheets/generic/forms.scss

 input[type='search'].search-text-input {
-  background-image: url("icon-search.png");
+  background-image: image-url("icon-search.png");
   background-repeat: no-repeat;
   background-position: 10px;
   padding-left: 25px;

app/assets/stylesheets/generic/typography.scss

@@ -105,7 +105,7 @@ a:focus {
       display: inline-block;
       width: $size;
       height: $size;
-      background-image: url("icon-link.png");
+      background-image: image-url("icon-link.png");
       background-size: contain;
       background-repeat: no-repeat;
     }

app/assets/stylesheets/sections/commits.scss

@@ -73,7 +73,7 @@
 
 
 .commits-compare-switch{
-  background: url("switch_icon.png") no-repeat center center;
+  background: image-url("switch_icon.png") no-repeat center center;
   width: 32px;
   height: 32px;
   text-indent: -9999px;

app/assets/stylesheets/sections/diff.scss

@@ -144,7 +144,7 @@
       line-height: 0;
       img{
         border: 1px solid #FFF;
-        background: url('trans_bg.gif');
+        background: image-url('trans_bg.gif');
         max-width: 100%;
       }
       &.deleted {
@@ -209,7 +209,7 @@
           width: 15px;
           position: absolute;
           top: 0px;
-          background: url('swipemode_sprites.gif') 0 3px no-repeat;
+          background: image-url('swipemode_sprites.gif') 0 3px no-repeat;
         }
         .bottom-handle{
           display: block;
@@ -217,7 +217,7 @@
           width: 15px;
           position: absolute;
           bottom: 0px;
-          background: url('swipemode_sprites.gif') 0 -11px no-repeat;
+          background: image-url('swipemode_sprites.gif') 0 -11px no-repeat;
         }
       }
     } //.view.swipe
@@ -249,7 +249,7 @@
           left: 12px;
           height: 10px;
           width: 276px;
-          background: url('onion_skin_sprites.gif') -4px -20px repeat-x;
+          background: image-url('onion_skin_sprites.gif') -4px -20px repeat-x;
         }
 
         .dragger {
@@ -259,7 +259,7 @@
           top: 0px;
           height: 14px;
           width: 14px;
-          background: url('onion_skin_sprites.gif') 0px -34px repeat-x;
+          background: image-url('onion_skin_sprites.gif') 0px -34px repeat-x;
           cursor: pointer;
         }
 
@@ -270,7 +270,7 @@
           right: 0px;
           height: 10px;
           width: 10px;
-          background: url('onion_skin_sprites.gif') -2px 0px no-repeat;
+          background: image-url('onion_skin_sprites.gif') -2px 0px no-repeat;
         }
 
         .opaque {
@@ -280,7 +280,7 @@
           left: 0px;
           height: 10px;
           width: 10px;
-          background: url('onion_skin_sprites.gif') -2px -10px no-repeat;
+          background: image-url('onion_skin_sprites.gif') -2px -10px no-repeat;
         }
       }
     } //.view.onion-skin

app/assets/stylesheets/sections/header.scss

@@ -161,7 +161,7 @@ header {
     }
 
     .search-input {
-      background-image: url("icon-search.png");
+      background-image: image-url("icon-search.png");
       background-repeat: no-repeat;
       background-position: 10px;
       height: inherit;

app/assets/stylesheets/sections/notes.scss

@@ -196,7 +196,7 @@ ul.notes {
 
 .diff-file tr.line_holder {
   .add-diff-note {
-    background: url("diff_note_add.png") no-repeat left 0;
+    background: image-url("diff_note_add.png") no-repeat left 0;
     height: 22px;
     margin-left: -65px;
     position: absolute;

app/helpers/application_helper.rb

@@ -54,7 +54,7 @@ module ApplicationHelper
     if group && group.avatar.present?
       group.avatar.url
     else
-      '/assets/no_group_avatar.png'
+      image_path('no_group_avatar.png')
     end
   end