Fix secret EditText display and other fixes.

+ Now it shows shadowed "(unchanged)" (as in wifi settings) and "(not set)"
  instead of two dots.

Patch Set 2:
+ Show cancellation confirmation dialog only when there's change in
  profile.

Patch Set 3:
+ Re-enable profile preferences when the reconnect dialog is cancelled.

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

@@ -27,6 +27,7 @@ import android.net.vpn.L2tpProfile;
 import android.net.vpn.VpnProfile;
 import android.net.vpn.VpnType;
 import android.os.Bundle;
+import android.os.Parcel;
 import android.os.Parcelable;
 import android.preference.PreferenceActivity;
 import android.preference.PreferenceGroup;
@@ -47,6 +48,7 @@ public class VpnEditor extends PreferenceActivity {
 
     private VpnProfileEditor mProfileEditor;
     private boolean mAddingProfile;
+    private byte[] mOriginalProfileData;
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
@@ -61,6 +63,10 @@ public class VpnEditor extends PreferenceActivity {
         addPreferencesFromResource(R.xml.vpn_edit);
 
         initViewFor(p);
+
+        Parcel parcel = Parcel.obtain();
+        p.writeToParcel(parcel, 0);
+        mOriginalProfileData = parcel.marshall();
     }
 
     @Override
@@ -90,7 +96,11 @@ public class VpnEditor extends PreferenceActivity {
                 return true;
 
             case MENU_CANCEL:
-                showCancellationConfirmDialog();
+                if (profileChanged()) {
+                    showCancellationConfirmDialog();
+                } else {
+                    finish();
+                }
                 return true;
         }
         return super.onOptionsItemSelected(item);
@@ -131,7 +141,7 @@ public class VpnEditor extends PreferenceActivity {
             return false;
         }
 
-        setResult(getProfile());
+        if (profileChanged()) setResult(getProfile());
         return true;
     }
 
@@ -177,4 +187,17 @@ public class VpnEditor extends PreferenceActivity {
     private VpnProfile getProfile() {
         return mProfileEditor.getProfile();
     }
+
+    private boolean profileChanged() {
+        Parcel newParcel = Parcel.obtain();
+        getProfile().writeToParcel(newParcel, 0);
+        byte[] newData = newParcel.marshall();
+        if (mOriginalProfileData.length == newData.length) {
+            for (int i = 0, n = mOriginalProfileData.length; i < n; i++) {
+                if (mOriginalProfileData[i] != newData[i]) return true;
+            }
+            return false;
+        }
+        return true;
+    }
 }