Add UI for the "invite"

- Add "More networks" button to the contact card networks section,
  which opens the list of invitable account types in a popup.
  (This "More networks" section reuses NetworkTitleViewEntry.)
- The list popup uses the same layout as the account selector
- Updated the account selector layout according to the rough visual
  spec.   Removed the tablet variant, as we use the same layout
  on the tablet too for now.
- Sends the invite intent when a type is selected.

Bug 5061956

Change-Id: I0a62126a0cf4ffeecc1a7263b124d00201b67e21
diff --git a/src/com/android/contacts/ContactLoader.java b/src/com/android/contacts/ContactLoader.java
index 4078598..3463d3c 100644
--- a/src/com/android/contacts/ContactLoader.java
+++ b/src/com/android/contacts/ContactLoader.java
@@ -730,6 +730,11 @@
             }
         }
 
+        /**
+         * Sets the "invitable" account types to {@link Result#mInvitableAccountTypes}.
+         *
+         * TODO Exclude the ones with no raw contacts in the database.
+         */
         private void loadInvitableAccountTypes(Result contactData) {
             Map<String, AccountType> allInvitables =
                     AccountTypeManager.getInstance(getContext()).getInvitableAccountTypes();