Move media attachment long-click event to context menu.

Long-click on a media attachment will now bring up the normal
context menu for a ConversationItem long-click, but with the
addition of a "save attachment" option.

This allows users to long-click on messages with media in them
and still see the other contextual menu options.

// FREEBIE

src/org/thoughtcrime/securesms/database/model/MediaMmsMessageRecord.java

@@ -68,6 +68,11 @@ public class MediaMmsMessageRecord extends MessageRecord {
     return true;
   }
 
+  @Override
+  public boolean isMmsNotification() {
+    return false;
+  }
+
   @Override
   public SpannableString getDisplayBody() {
     if (MmsDatabase.Types.isDecryptInProgressType(type)) {

src/org/thoughtcrime/securesms/database/model/MessageRecord.java

@@ -62,6 +62,7 @@ public abstract class MessageRecord extends DisplayRecord {
   }
 
   public abstract boolean isMms();
+  public abstract boolean isMmsNotification();
 
   public boolean isFailed() {
     return

src/org/thoughtcrime/securesms/database/model/NotificationMmsMessageRecord.java

@@ -101,6 +101,11 @@ public class NotificationMmsMessageRecord extends MessageRecord {
     return true;
   }
 
+  @Override
+  public boolean isMmsNotification() {
+    return true;
+  }
+
   @Override
   public SpannableString getDisplayBody() {
     return emphasisAdded(context.getString(R.string.NotificationMmsMessageRecord_multimedia_message));

src/org/thoughtcrime/securesms/database/model/SmsMessageRecord.java

@@ -98,6 +98,11 @@ public class SmsMessageRecord extends MessageRecord {
     return false;
   }
 
+  @Override
+  public boolean isMmsNotification() {
+    return false;
+  }
+
   private static int getGenericDeliveryStatus(int status) {
     if (status == SmsDatabase.Status.STATUS_NONE) {
       return MessageRecord.DELIVERY_STATUS_NONE;