[Cleanup] Move all browsertests to use ScopedFeatureList to modify features

chrome/browser/plugins/flash_permission_browsertest.cc

Index: chrome/browser/plugins/flash_permission_browsertest.cc
diff --git a/chrome/browser/plugins/flash_permission_browsertest.cc b/chrome/browser/plugins/flash_permission_browsertest.cc
index 508190b781429b86275a16e6852ea600640664cd..a18e15df9552f4a0a8e487ea64b512c069b6928c 100644
--- a/chrome/browser/plugins/flash_permission_browsertest.cc
+++ b/chrome/browser/plugins/flash_permission_browsertest.cc
@@ -7,8 +7,10 @@
 #include "base/memory/ptr_util.h"
 #include "base/path_service.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/scoped_feature_list.h"
 #include "chrome/browser/permissions/permissions_browsertest.h"
 #include "chrome/browser/ui/permission_bubble/mock_permission_prompt_factory.h"
+#include "chrome/common/chrome_features.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/test/base/ui_test_utils.h"
 #include "components/variations/variations_switches.h"
@@ -53,15 +55,11 @@ class FlashPermissionBrowserTest : public PermissionsBrowserTest {
 
     ASSERT_TRUE(ppapi::RegisterFlashTestPlugin(command_line));
 
+#if BUILDFLAG(ENABLE_PLUGINS)

[Ilya Sherman, 2017/06/12 21:50:29]

Why did you add this #if wrapper?

[chaopeng, 2017/06/28 19:21:24]

This feature only define when enable plugins.
https://cs.chromium.org/chromium/src/chrome/common/chrome_features.cc?rcl=239...

     // Set a high engagement threshhold so it doesn't interfere with testing the
     // permission.

[Ilya Sherman, 2017/06/12 21:50:29]

Why did you drop the setting of the param?

[chaopeng, 2017/06/28 19:21:24]

Done.

-    command_line->AppendSwitchASCII(switches::kEnableFeatures,
-                                    "PreferHtmlOverPlugins<Study1");
-    command_line->AppendSwitchASCII(switches::kForceFieldTrials,
-                                    "Study1/Enabled/");
-    command_line->AppendSwitchASCII(
-        variations::switches::kForceFieldTrialParams,
-        "Study1.Enabled:engagement_threshold_for_flash/100");
+    scoped_feature_list_.InitAndEnableFeature(features::kPreferHtmlOverPlugins);
+#endif
   }
 
   void TriggerPrompt() override {
@@ -95,6 +93,9 @@ class FlashPermissionBrowserTest : public PermissionsBrowserTest {
     return RunScriptReturnBool("flashIsEnabled();") ||
            RunScriptReturnBool("flashIsEnabledForPluginWithoutFallback();");
   }
+
+ private:
+  base::test::ScopedFeatureList scoped_feature_list_;
 };
 
 IN_PROC_BROWSER_TEST_F(FlashPermissionBrowserTest,