Add deprecation warnings for permission API usage from iframes

third_party/WebKit/public/platform/WebFeaturePolicyFeature.h

 // Copyright 2017 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.
 
 #ifndef WebFeaturePolicyFeature_h
 #define WebFeaturePolicyFeature_h
 
 namespace blink {
 
 // These values map to the features which can be controlled by Feature Policy.
 //
 // Features are defined in
-// https://wicg.github.io/feature-policy/#defined-features. Many of these are
-// still under development in blink behind the featurePolicyExperimentalFeatures
-// flag, see getWebFeaturePolicyFeature().
+// https://github.com/WICG/feature-policy/blob/gh-pages/features.md. Many of
+// these are still under development in blink behind the
+// featurePolicyExperimentalFeatures flag, see getWebFeaturePolicyFeature().
 enum class WebFeaturePolicyFeature {
   kNotFound = 0,
   // Controls access to video input devices.
   kCamera,
   // Controls whether navigator.requestMediaKeySystemAccess is allowed.
   kEme,
   // Controls whether Element.requestFullscreen is allowed.
   kFullscreen,
   // Controls access to Geolocation interface.
   kGeolocation,
@@ skipping 18 matching lines @@
   // Controls use of synchronous XMLHTTPRequest API.
   kSyncXHR,
   // Controls access to the WebUSB API.
   kUsb,
   LAST_FEATURE = kUsb
 };
 
 }  // namespace blink
 
 #endif  // WebFeaturePolicyFeature_h