git-codereview: call testMain instead of executing "git codereview ..."

Fixes #9648

Change-Id: I86995c262fee31eb17c1dcb6c9e48fe632b78cf0
Reviewed-on: https://go-review.googlesource.com/6425
Reviewed-by: Russ Cox <rsc@golang.org>
diff --git a/git-codereview/gofmt_test.go b/git-codereview/gofmt_test.go
index de2aae6..b9cd7b9 100644
--- a/git-codereview/gofmt_test.go
+++ b/git-codereview/gofmt_test.go
@@ -265,7 +265,7 @@
 	// update client
 	trun(t, gt.client, "git", "checkout", "master")
 	trun(t, gt.client, "git", "pull")
-	trun(t, gt.client, "git", "codereview", "change", "dev.branch")
+	testMain(t, "change", "dev.branch")
 	trun(t, gt.client, "git", "pull")
 
 	// merge master into dev.branch, fast forward merge
diff --git a/git-codereview/hook_test.go b/git-codereview/hook_test.go
index 27df0d0..645c547 100644
--- a/git-codereview/hook_test.go
+++ b/git-codereview/hook_test.go
@@ -117,19 +117,19 @@
 	// Test that commit hook adds prefix.
 	trun(t, gt.server, "git", "checkout", "-b", "dev.cc")
 	trun(t, gt.client, "git", "fetch", "-q")
-	trun(t, gt.client, "git", "codereview", "change", "dev.cc")
+	testMain(t, "change", "dev.cc")
 	checkPrefix("[dev.cc] Test message.\n")
 
 	// Work branch with server branch as upstream.
-	trun(t, gt.client, "git", "codereview", "change", "ccwork")
+	testMain(t, "change", "ccwork")
 	checkPrefix("[dev.cc] Test message.\n")
 
 	// Master has no prefix.
-	trun(t, gt.client, "git", "codereview", "change", "master")
+	testMain(t, "change", "master")
 	checkPrefix("Test message.\n")
 
 	// Work branch from master has no prefix.
-	trun(t, gt.client, "git", "codereview", "change", "work")
+	testMain(t, "change", "work")
 	checkPrefix("Test message.\n")
 }