DevTools: only allow status bar items in status bars.

Source/devtools/front_end/resources/indexedDBViews.css

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 41 matching lines @@
 .indexed-db-database-view .outline-disclosure .attribute-value {
     display: inline;
     margin-top: 1px;
 }
 
 .indexed-db-data-view .data-view-toolbar {
     position: relative;
     border-top: none;
     height: 24px;
     padding: 1px;
+    background-color: #eee;
+    border-bottom: 1px solid #ccc;
 }
 
 .indexed-db-data-view .data-grid-container {
     top: 24px;
 }
 
-.indexed-db-data-view .data-view-toolbar .back-button img {
-    content: url(Images/back.png);
+.indexed-db-status-bar-back-button,
+.indexed-db-status-bar-forward-button {
+    background-repeat: no-repeat;
+    border: 3px solid transparent;
 }
 
-.indexed-db-data-view .data-view-toolbar .forward-button img {
-    content: url(Images/forward.png);
+.indexed-db-status-bar-back-button:disabled,
+.indexed-db-status-bar-forward-button:disabled {
+    opacity: 0.5;
+}
+
+.indexed-db-status-bar-back-button {
+    background-image: url(Images/back.png);
+}
+
+.indexed-db-status-bar-forward-button {
+    background-image: url(Images/forward.png);
+}
+
+.indexed-db-status-bar-back-button .glyph,
+.indexed-db-status-bar-forward-button .glyph {
+    display: none;
 }
 
 .indexed-db-data-view .data-view-toolbar .key-input {
     font-size: 11px;
     margin: auto 0;
     width: 200px;
 }
 
 .indexed-db-data-view .data-grid {
     height: 100%;
@@ skipping 26 matching lines @@
 
 .indexed-db-data-view .primitive-value {
     padding-top: 1px;
 }
 
 .indexed-db-data-view .data-grid .data-container td .section .header .title {
     white-space: nowrap;
     text-overflow: ellipsis;
     overflow: hidden;
 }