Switch from 'Contents Hidden' to 'New message'

Fixes #4004
Closes #4566

res/values/strings.xml

@@ -580,8 +580,8 @@
     <string name="QuickResponseService_problem_sending_message">Problem sending message!</string>
 
     <!-- SingleRecipientNotificationBuilder -->
-    <string name="SingleRecipientNotificationBuilder_new_signal_message">New Signal message</string>
-    <string name="SingleRecipientNotificationBuilder_contents_hidden">Contents hidden</string>
+    <string name="SingleRecipientNotificationBuilder_signal">Signal</string>
+    <string name="SingleRecipientNotificationBuilder_new_message">New Message!</string>
 
     <!-- attachment_type_selector -->
     <string name="attachment_type_selector__image">Image</string>

src/org/thoughtcrime/securesms/notifications/SingleRecipientNotificationBuilder.java

@@ -65,7 +65,7 @@ public class SingleRecipientNotificationBuilder extends AbstractNotificationBuil
                             .asDrawable(context, recipient.getColor()
                                                           .toConversationColor(context)));
     } else {
-      setContentTitle(context.getString(R.string.SingleRecipientNotificationBuilder_new_signal_message));
+      setContentTitle(context.getString(R.string.SingleRecipientNotificationBuilder_signal));
       setLargeIcon(Recipient.getUnknownRecipient()
                             .getContactPhoto()
                             .asDrawable(context, Recipient.getUnknownRecipient()
@@ -84,7 +84,7 @@ public class SingleRecipientNotificationBuilder extends AbstractNotificationBuil
       setContentText(message);
       this.slideDeck = slideDeck;
     } else {
-      setContentText(context.getString(R.string.SingleRecipientNotificationBuilder_contents_hidden));
+      setContentText(context.getString(R.string.SingleRecipientNotificationBuilder_new_message));
     }
   }
 
@@ -131,9 +131,9 @@ public class SingleRecipientNotificationBuilder extends AbstractNotificationBuil
     if (privacy.isDisplayMessage()) {
       setTicker(getStyledMessage(recipient, message));
     } else if (privacy.isDisplayContact()) {
-      setTicker(getStyledMessage(recipient, context.getString(R.string.SingleRecipientNotificationBuilder_new_signal_message)));
+      setTicker(getStyledMessage(recipient, context.getString(R.string.SingleRecipientNotificationBuilder_new_message)));
     } else {
-      setTicker(context.getString(R.string.SingleRecipientNotificationBuilder_new_signal_message));
+      setTicker(context.getString(R.string.SingleRecipientNotificationBuilder_new_message));
     }
   }