LayoutLib: Add capability to simulate old versions

Let the IDE know that we can simulate older versions of platform.

Change-Id: Idec6d24296dd0ae04a2d808c14604629e265d458

tools/layoutlib/bridge/src/com/android/layoutlib/bridge/Bridge.java

@@ -214,7 +214,8 @@ public final class Bridge extends com.android.ide.common.rendering.api.Bridge {
                 Capability.EXTENDED_VIEWINFO,
                 Capability.FIXED_SCALABLE_NINE_PATCH,
                 Capability.RTL,
-                Capability.ACTION_BAR);
+                Capability.ACTION_BAR,
+                Capability.SIMULATE_PLATFORM);
 
 
         BridgeAssetManager.initSystem();