rename REPO_DOWNLOAD to REPO

The "download" suffix is redundant and reflects how `repo` used to
be used in the download plugin -- as kind of a pseudo download
bolted onto the side.  Since we've reworked the plugin, we can
rename this constant to better reflect its usage.

Change-Id: I0b094d971a8591a46b1b1f05cbbfe32e8483f207
diff --git a/src/main/java/com/googlesource/gerrit/plugins/download/scheme/RepoScheme.java b/src/main/java/com/googlesource/gerrit/plugins/download/scheme/RepoScheme.java
index 17f651f..7b5ddef 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/download/scheme/RepoScheme.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/download/scheme/RepoScheme.java
@@ -14,7 +14,7 @@
 
 package com.googlesource.gerrit.plugins.download.scheme;
 
-import static com.google.gerrit.entities.CoreDownloadSchemes.REPO_DOWNLOAD;
+import static com.google.gerrit.entities.CoreDownloadSchemes.REPO;
 
 import com.google.gerrit.extensions.config.DownloadScheme;
 import com.google.gerrit.server.config.DownloadConfig;
@@ -25,7 +25,7 @@
 
   @Inject
   RepoScheme(DownloadConfig downloadConfig) {
-    this.schemeAllowed = downloadConfig.getDownloadSchemes().contains(REPO_DOWNLOAD);
+    this.schemeAllowed = downloadConfig.getDownloadSchemes().contains(REPO);
   }
 
   @Override