Add flag to force touch events to be passive during fling as a runtime feature

chrome/browser/about_flags.cc

 // Copyright (c) 2012 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/about_flags.h"
 
 #include <iterator>
 #include <map>
 #include <set>
 #include <utility>
@@ skipping 1988 matching lines @@
      IDS_FLAGS_EXPERIMENTAL_POINTER_EVENT_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kPointerEvents)},
     {"passive-listener-default",  // FLAGS:RECORD_UMA
      IDS_FLAGS_PASSIVE_EVENT_LISTENER_DEFAULT_NAME,
      IDS_FLAGS_PASSIVE_EVENT_LISTENER_DEFAULT_DESCRIPTION, kOsAll,
      MULTI_VALUE_TYPE(kPassiveListenersChoices)},
     {"document-passive-event-listeners",  // FLAGS:RECORD_UMA
      IDS_FLAGS_PASSIVE_DOCUMENT_EVENT_LISTENERS_NAME,
      IDS_FLAGS_PASSIVE_DOCUMENT_EVENT_LISTENERS_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kPassiveDocumentEventListeners)},
+    {"passive-event-listeners-due-to-fling",  // FLAGS:RECORD_UMA
+     IDS_FLAGS_PASSIVE_EVENT_LISTENERS_DUE_TO_FLING_NAME,
+     IDS_FLAGS_PASSIVE_EVENT_LISTENERS_DUE_TO_FLING_DESCRIPTION, kOsAll,
+     FEATURE_VALUE_TYPE(features::kPassiveEventListenersDueToFling)},
     {"enable-loading-ipc-optimization-for-small-resources",
      IDS_FLAGS_OPTIMIZE_LOADING_IPC_FOR_SMALL_RESOURCES_NAME,
      IDS_FLAGS_OPTIMIZE_LOADING_IPC_FOR_SMALL_RESOURCES_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kOptimizeLoadingIPCForSmallResources)},
     {"enable-font-cache-scaling", IDS_FLAGS_FONT_CACHE_SCALING_NAME,
      IDS_FLAGS_FONT_CACHE_SCALING_DESCRIPTION, kOsAll,
      FEATURE_VALUE_TYPE(features::kFontCacheScaling)},
 #if defined(OS_ANDROID)
     {"enable-vr-shell", IDS_FLAGS_ENABLE_VR_SHELL_NAME,
      IDS_FLAGS_ENABLE_VR_SHELL_DESCRIPTION, kOsAndroid,
@@ skipping 216 matching lines @@
 const base::HistogramBase::Sample kBadSwitchFormatHistogramId = 0;
 
 const FeatureEntry* GetFeatureEntries(size_t* count) {
   *count = arraysize(kFeatureEntries);
   return kFeatureEntries;
 }
 
 }  // namespace testing
 
 }  // namespace about_flags