Replace --add-to-shelf flag with kAppBanners feature.

chrome/browser/installable/installable_manager_browsertest.cc

Index: chrome/browser/installable/installable_manager_browsertest.cc
diff --git a/chrome/browser/installable/installable_manager_browsertest.cc b/chrome/browser/installable/installable_manager_browsertest.cc
index d7c9b70e0d6f3e498cd070234f3bf85e69fcf551..e59dbe3cca572f66aea0c11df0f86bc7c6b035a8 100644
--- a/chrome/browser/installable/installable_manager_browsertest.cc
+++ b/chrome/browser/installable/installable_manager_browsertest.cc
@@ -7,10 +7,11 @@
 #include "base/command_line.h"
 #include "base/memory/ptr_util.h"
 #include "base/run_loop.h"
+#include "base/test/scoped_feature_list.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/ui/browser.h"
 #include "chrome/browser/ui/tabs/tab_strip_model.h"
-#include "chrome/common/chrome_switches.h"
+#include "chrome/common/chrome_features.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "content/public/test/browser_test_utils.h"
@@ -178,6 +179,10 @@ class InstallableManagerBrowserTest : public InProcessBrowserTest {
   void SetUpOnMainThread() override {
     InProcessBrowserTest::SetUpOnMainThread();
     ASSERT_TRUE(embedded_test_server()->Start());
+
+    // Make sure app banners are disabled in the browser so they do not
+    // interfere with the test.
+    feature_list_.InitAndDisableFeature(features::kAppBanners);

[Ilya Sherman, 2017/06/22 16:36:22]

I'm not 100% sure, but I think this might be running too late to have any
effect.  Did you verify that removing this line affects how the test runs?

[benwells, 2017/06/23 02:09:26]

There is no problem with this, it does affect the tests in the correct way. It
isn't very clear to do it via a feature though, I have another patch lined up
which does this same thing with a static ForTesting style method.

   }
 
   // Returns a test server URL to a page controlled by a service worker with
@@ -204,12 +209,6 @@ class InstallableManagerBrowserTest : public InProcessBrowserTest {
                                 base::Unretained(tester)));
   }
 
-  void SetUpCommandLine(base::CommandLine* command_line) override {
-    // Make sure app banners are disabled in the browser so they do not
-    // interfere with the test.
-    command_line->AppendSwitch(switches::kDisableAddToShelf);
-  }
-
   InstallableManager* GetManager() {
     content::WebContents* web_contents =
         browser()->tab_strip_model()->GetActiveWebContents();
@@ -222,6 +221,9 @@ class InstallableManagerBrowserTest : public InProcessBrowserTest {
   }
 
   InstallabilityCheckStatus GetStatus() { return GetManager()->page_status_; }
+
+ private:
+  base::test::ScopedFeatureList feature_list_;
 };
 
 IN_PROC_BROWSER_TEST_F(InstallableManagerBrowserTest,