DRY out set config of Git protocol v2 in tests

The configuration of Git protocol v2 in the target
projects can be refactored to a common method in
GitProtocolV2IT.java, making the code more readable
and without the need of extra comments on the
statement.

Change-Id: I8a65b6df3a6fe072562de64ec0441046f1caa52c
diff --git a/javatests/com/google/gerrit/integration/git/GitProtocolV2IT.java b/javatests/com/google/gerrit/integration/git/GitProtocolV2IT.java
index 76ce956..3068003 100644
--- a/javatests/com/google/gerrit/integration/git/GitProtocolV2IT.java
+++ b/javatests/com/google/gerrit/integration/git/GitProtocolV2IT.java
@@ -98,10 +98,7 @@
                   .group(SystemGroupBackend.REGISTERED_USERS))
           .update();
 
-      // Set protocol.version=2 in target repository
-      execute(
-          ImmutableList.of("git", "config", "protocol.version", "2"),
-          sitePaths.site_path.resolve("git").resolve(project.get() + Constants.DOT_GIT).toFile());
+      setProtocolV2(project);
 
       // Retrieve HTTP url
       String url = config.getString("gerrit", null, "canonicalweburl");
@@ -217,14 +214,7 @@
       Project.NameKey allRefsVisibleProject = Project.nameKey("all-refs-visible");
       gApi.projects().create(allRefsVisibleProject.get());
 
-      // Set protocol.version=2 in target repository
-      execute(
-          ImmutableList.of("git", "config", "protocol.version", "2"),
-          sitePaths
-              .site_path
-              .resolve("git")
-              .resolve(allRefsVisibleProject.get() + Constants.DOT_GIT)
-              .toFile());
+      setProtocolV2(allRefsVisibleProject);
 
       // Set up project permission to allow reading all refs
       projectOperations
@@ -280,14 +270,7 @@
       Project.NameKey privateProject = Project.nameKey("private-project");
       gApi.projects().create(privateProject.get());
 
-      // Set protocol.version=2 in target repository
-      execute(
-          ImmutableList.of("git", "config", "protocol.version", "2"),
-          sitePaths
-              .site_path
-              .resolve("git")
-              .resolve(privateProject.get() + Constants.DOT_GIT)
-              .toFile());
+      setProtocolV2(privateProject);
 
       // Disallow general read permissions for anonymous users
       projectOperations
@@ -356,6 +339,12 @@
                 UTF_8));
   }
 
+  private void setProtocolV2(Project.NameKey projectName) throws Exception {
+    execute(
+        ImmutableList.of("git", "config", "protocol.version", "2"),
+        sitePaths.site_path.resolve("git").resolve(projectName.get() + Constants.DOT_GIT).toFile());
+  }
+
   private static void assertGitProtocolV2Refs(String commit, String out) {
     assertThat(out).contains("git< version 2");
     assertThat(out).contains("refs/changes/01/1/1");