Handle popup exceptions in mergePermissionInfoForTopLevelOrigin

This patch fixes Site Settings on Android to properly display popup
exceptions. This fixes a regression from an earlier patch that made
drilling down from single category permissions show all permissions
(bug 673620), which made it impossible to clear popup exceptions on
any individual site.

Bug: 791897, 763982
Change-Id: Ib1383289c8f7e0fb3643a9ad0a8ef0f7c3f3b137
Reviewed-on: https://chromium-review.googlesource.com/810224Reviewed-by: Finnur Thorarinsson <finnur@chromium.org>
Commit-Queue: Timothy Loh <timloh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#522300}

chrome/android/java/src/org/chromium/chrome/browser/preferences/website/SingleWebsitePreferences.java

@@ -255,13 +255,14 @@ public class SingleWebsitePreferences extends PreferenceFragment
                         && other.getBackgroundSyncException() != null) {
                     merged.setBackgroundSyncException(other.getBackgroundSyncException());
                 }
+                if (merged.getPopupException() == null && other.getPopupException() != null) {
+                    merged.setPopupException(other.getPopupException());
+                }
             }
 
             // TODO(crbug.com/763982): Deal with this TODO colony.
             // TODO(mvanouwerkerk): Make the various info types share a common interface that
             // supports reading the origin or host.
-            // TODO(mvanouwerkerk): Merge in PopupExceptionInfo? It uses a pattern, and is never
-            // set on Android.
             // TODO(lshang): Merge in CookieException? It will use patterns.
         }
         return merged;