[Extensions] Clean up renderer channel-related code

extensions/shell/test/shell_test.cc

Index: extensions/shell/test/shell_test.cc
diff --git a/extensions/shell/test/shell_test.cc b/extensions/shell/test/shell_test.cc
index b1e8cc4093c52966772ee286922917909de9fd6c..96ebb2a69441fd8adaee050cd2cafb93f0d97113 100644
--- a/extensions/shell/test/shell_test.cc
+++ b/extensions/shell/test/shell_test.cc
@@ -10,6 +10,7 @@
 #include "base/logging.h"
 #include "base/path_service.h"
 #include "build/build_config.h"
+#include "components/version_info/version_info.h"
 #include "content/public/common/content_switches.h"
 #include "extensions/browser/extension_system.h"
 #include "extensions/shell/browser/desktop_controller.h"
@@ -18,7 +19,12 @@
 
 namespace extensions {
 
-AppShellTest::AppShellTest() : browser_context_(NULL), extension_system_(NULL) {
+AppShellTest::AppShellTest()
+    : browser_context_(nullptr),
+      extension_system_(nullptr),
+      // Default channel is STABLE but override with UNKNOWN so that unlaunched
+      // or incomplete APIs can write tests.
+      current_channel_(version_info::Channel::UNKNOWN) {
 #if defined(OS_MACOSX)
   // TODO(phajdan.jr): Make browser tests self-contained on Mac; remove this.
   // Set up the application path as though we we are inside the App Shell.app