Handle fragment breadcrumbs for deep-linked settings launches.

This adds meta-data to the manifest for specifying the parent fragment and enabling a link
in the breadcrumbs to navigate "up" a level even if the parent is not in the back-stack.

Bug: 3236568

Fix a monkey issue in VpnSettings.

src/com/android/settings/vpn/VpnSettings.java

@@ -196,6 +196,17 @@ public class VpnSettings extends SettingsPreferenceFragment
         super.onDestroyView();
     }
 
+    @Override
+    public void onDestroy() {
+        super.onDestroy();
+        // Remove any onClick listeners
+        if (mVpnListContainer != null) {
+            for (int i = 0; i < mVpnListContainer.getPreferenceCount(); i++) {
+                mVpnListContainer.getPreference(i).setOnPreferenceClickListener(null);
+            }
+        }
+    }
+
     @Override
     public Dialog onCreateDialog (int id) {
         switch (id) {
@@ -1050,6 +1061,7 @@ public class VpnSettings extends SettingsPreferenceFragment
                             changeState(p, VpnState.IDLE);
                         }
                     }
+                    if (getActivity() == null) return;
                     getActivity().unbindService(this);
                     showPreferences();
                 }
@@ -1058,6 +1070,7 @@ public class VpnSettings extends SettingsPreferenceFragment
                     cv.open();
 
                     setDefaultState(list);
+                    if (getActivity() == null) return;
                     getActivity().unbindService(this);
                     showPreferences();
                 }