make NavigationGesture part of public content API and use it outside content

chrome/browser/plugins/flash_download_interception_unittest.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 "chrome/browser/plugins/flash_download_interception.h"
 
 #include "base/test/scoped_feature_list.h"
 #include "chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "chrome/common/chrome_features.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
@@ skipping 71 matching lines @@
 TEST_F(FlashDownloadInterceptionTest, NavigationThrottleCancelsNavigation) {
   base::test::ScopedFeatureList feature_list;
   feature_list.InitAndEnableFeature(features::kPreferHtmlOverPlugins);
 
   // Set the source URL to an HTTP source.
   NavigateAndCommit(GURL("http://example.com"));
 
   std::unique_ptr<NavigationHandle> handle =
       NavigationHandle::CreateNavigationHandleForTesting(
           GURL("https://get.adobe.com/flashplayer"), main_rfh(),
-          false /* committed */, net::OK, true /* has_user_gesture */);
+          false /* committed */, net::OK, content::NavigationGestureUser);
 
   handle->CallWillStartRequestForTesting(true, content::Referrer(),
                                          ui::PAGE_TRANSITION_LINK, false);
   std::unique_ptr<NavigationThrottle> throttle =
       FlashDownloadInterception::MaybeCreateThrottleFor(handle.get());
   EXPECT_NE(nullptr, throttle);
   ASSERT_EQ(NavigationThrottle::CANCEL_AND_IGNORE,
             throttle->WillStartRequest());
 }
 
@@ skipping 16 matching lines @@
   // Intercept on both explicit DETECT and BLOCK.
   map->SetDefaultContentSetting(CONTENT_SETTINGS_TYPE_PLUGINS,
                                 CONTENT_SETTING_BLOCK);
   EXPECT_TRUE(
       ShouldStopFlashDownloadAction("https://get.adobe.com/flashplayer/"));
   map->SetDefaultContentSetting(CONTENT_SETTINGS_TYPE_PLUGINS,
                                 CONTENT_SETTING_DETECT_IMPORTANT_CONTENT);
   EXPECT_TRUE(
       ShouldStopFlashDownloadAction("https://get.adobe.com/flashplayer/"));
 }