Fix ripple being shown on non-selactable prefs

Bug: 26759079
Change-Id: I59519cb97374123ebe9cec03f4bd7c021378ef1c
diff --git a/v7/preference/src/android/support/v7/preference/Preference.java b/v7/preference/src/android/support/v7/preference/Preference.java
index 6c7f909..175f855 100644
--- a/v7/preference/src/android/support/v7/preference/Preference.java
+++ b/v7/preference/src/android/support/v7/preference/Preference.java
@@ -529,6 +529,7 @@
 
         final boolean selectable = isSelectable();
         holder.itemView.setFocusable(selectable);
+        holder.itemView.setClickable(selectable);
 
         holder.setDividerAllowedAbove(selectable);
         holder.setDividerAllowedBelow(selectable);