[Native Filesystem] Rename base::Feature and add it to chrome://flags

Bug: 929490, 853326
Change-Id: Ie2149b7a753d95c02067fcd1ff13c6c03426953a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1501574
Reviewed-by: Lei Zhang <[email protected]>
Reviewed-by: Elly Fong-Jones <[email protected]>
Reviewed-by: Victor Costan <[email protected]>
Reviewed-by: Kentaro Hara <[email protected]>
Commit-Queue: Marijn Kruisselbrink <[email protected]>
Cr-Commit-Position: refs/heads/master@{#637851}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 5efd5a0..93b418ae 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -740,6 +740,9 @@
 extern const char kMobileIdentityConsistencyName[];
 extern const char kMobileIdentityConsistencyDescription[];
 
+extern const char kNativeFilesystemAPIName[];
+extern const char kNativeFilesystemAPIDescription[];
+
 extern const char kNewAudioRenderingMixingStrategyName[];
 extern const char kNewAudioRenderingMixingStrategyDescription[];