[MD settings] omit embeddingOrigin for site exceptions

This CL changes how the embeddingOrigin is set on content exceptions.
This is now more like it was done in the old options, where the
embedding origin was not sent from JavaScript.

BUG=714584
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:closure_compilation

Review-Url: https://codereview.chromium.org/2848933003
Cr-Commit-Position: refs/heads/master@{#468199}

chrome/browser/resources/settings/site_settings/site_settings_prefs_browser_proxy.js

@@ -326,15 +326,20 @@ cr.define('settings', function() {
     /** @override */
     resetCategoryPermissionForOrigin: function(
         primaryPattern, secondaryPattern, contentType, incognito) {
-      chrome.send('resetCategoryPermissionForOrigin',
+      chrome.send(
+          'resetCategoryPermissionForOrigin',
           [primaryPattern, secondaryPattern, contentType, incognito]);
     },
 
     /** @override */
     setCategoryPermissionForOrigin: function(
         primaryPattern, secondaryPattern, contentType, value, incognito) {
-      chrome.send('setCategoryPermissionForOrigin',
-          [primaryPattern, secondaryPattern, contentType, value, incognito]);
+      // TODO(dschuyler): It may be incorrect for JS to send the embeddingOrigin
+      // pattern. Look into removing this parameter from site_settings_handler.
+      // Ignoring the |secondaryPattern| and using '' instead is a quick-fix.
+      chrome.send(
+          'setCategoryPermissionForOrigin',
+          [primaryPattern, '', contentType, value, incognito]);
     },
 
     /** @override */