Revert of Remove enable/disable wheel gestures setting.

content/browser/renderer_host/input/non_blocking_event_browsertest.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <utility>
 
 #include "base/auto_reset.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/macros.h"
@@ skipping 91 matching lines @@
     host->GetView()->SetSize(gfx::Size(400, 400));
 
     base::string16 ready_title(base::ASCIIToUTF16("ready"));
     TitleWatcher watcher(shell()->web_contents(), ready_title);
     ignore_result(watcher.WaitAndGetTitle());
 
     MainThreadFrameObserver main_thread_sync(host);
     main_thread_sync.Wait();
   }
 
+  // ContentBrowserTest:
+  void SetUpCommandLine(base::CommandLine* cmd) override {
+    // TODO(dtapuska): Remove this switch once wheel-gestures ships.
+    cmd->AppendSwitch(switches::kEnableExperimentalWebPlatformFeatures);
+    cmd->AppendSwitch(switches::kEnableWheelGestures);
+  }
+
   int ExecuteScriptAndExtractInt(const std::string& script) {
     int value = 0;
     EXPECT_TRUE(content::ExecuteScriptAndExtractInt(
         shell()->web_contents(), "domAutomationController.send(" + script + ")",
         &value));
     return value;
   }
 
   int GetScrollTop() {
     return ExecuteScriptAndExtractInt("document.scrollingElement.scrollTop");
@@ skipping 80 matching lines @@
 #define MAYBE_PassiveTouchStartBlockingTouchEnd \
   PassiveTouchStartBlockingTouchEnd
 #endif
 IN_PROC_BROWSER_TEST_F(NonBlockingEventBrowserTest,
                        MAYBE_PassiveTouchStartBlockingTouchEnd) {
   LoadURL(kPassiveTouchStartBlockingTouchEndDataURL);
   DoTouchScroll();
 }
 
 }  // namespace content