[Extensions] Add a ScopedCurrentChannel to ExtensionActionAPIUnitTest

The "action" key is restricted to trunk, so we need to override the
current channel for these tests.

Tbr: lazyboy@chromium.org (trivial test fix)
Bug: 1067187, 893373
Change-Id: Iabb96a414e532a457007ca3cd453838cf3ea73aa
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2133874Reviewed-by: Devlin <rdevlin.cronin@chromium.org>
Commit-Queue: Devlin <rdevlin.cronin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#755835}

chrome/browser/extensions/api/extension_action/extension_action_api_unittest.cc

@@ -2,11 +2,15 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include <memory>
+
 #include "base/files/file_util.h"
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_service_test_with_install.h"
 #include "chrome/common/extensions/api/extension_action/action_info.h"
+#include "chrome/common/extensions/extension_test_util.h"
+#include "extensions/common/features/feature_channel.h"
 #include "extensions/common/manifest_constants.h"
 #include "extensions/test/test_extension_dir.h"
 
@@ -17,7 +21,9 @@ class ExtensionActionAPIUnitTest
     : public ExtensionServiceTestWithInstall,
       public ::testing::WithParamInterface<ActionInfo::Type> {
  public:
-  ExtensionActionAPIUnitTest() {}
+  ExtensionActionAPIUnitTest()
+      : current_channel_(
+            extension_test_util::GetOverrideChannelForActionType(GetParam())) {}
   ~ExtensionActionAPIUnitTest() override {}
 
   const char* GetManifestKey() {
@@ -47,6 +53,8 @@ class ExtensionActionAPIUnitTest
   }
 
  private:
+  std::unique_ptr<ScopedCurrentChannel> current_channel_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionActionAPIUnitTest);
 };