[MD Extensions] Include the manifest code snippet in load errors

chrome/browser/resources/md_extensions/code_section.js

Index: chrome/browser/resources/md_extensions/code_section.js
diff --git a/chrome/browser/resources/md_extensions/code_section.js b/chrome/browser/resources/md_extensions/code_section.js
index d0a93e2aac26986641c78f2ba764867322b36546..502c86dc1fffea9e53fba639fb71bef9c0751e92 100644
--- a/chrome/browser/resources/md_extensions/code_section.js
+++ b/chrome/browser/resources/md_extensions/code_section.js
@@ -21,10 +21,22 @@ cr.define('extensions', function() {
       },
 
       /**
-       * The string to display if no code is set.
+       * The string to display if no |code| is set (e.g. because we couldn't
+       * load the relevant source file).
        * @type {string}
        */
-      noCodeError: String,
+      couldNotDisplayCode: String,
+    },
+
+    /**
+     * Returns true if no code could be displayed (e.g. because the file could
+     * not be loaded).
+     * @return {boolean}
+     */
+    isEmpty: function() {
+      return !this.code ||
+             (!this.code.beforeHighlight && !this.code.highlight &&
+              !this.code.afterHighlight);
     },
 
     /**
@@ -46,14 +58,6 @@ cr.define('extensions', function() {
         textContent += i + '\n';
       return textContent;
     },
-
-    /**
-     * @return {boolean}
-     * @private
-     */
-    isMainHidden_: function() {
-      return !this.code;
-    },
   });
 
   return {CodeSection: CodeSection};