Move experimental accessibility feature flag from chromeos to ui/accessibility.

This is to allow us to use the flag within ui/accessibility, as
ui/accessibility cannot depend on chromeos/ or chrome/

BUG=889370
R=dmazzoni,aboxhall

Change-Id: I90c51f123c347975d1bc4ede3ea3900dac04625c
Reviewed-on: https://chromium-review.googlesource.com/c/1314072
Reviewed-by: Dominic Mazzoni <[email protected]>
Reviewed-by: Michael Giuffrida <[email protected]>
Reviewed-by: Scott Violet <[email protected]>
Commit-Queue: Chris Hall <[email protected]>
Cr-Commit-Position: refs/heads/master@{#605618}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 74749ca..a492f94 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -155,6 +155,9 @@
 extern const char kCloudPrinterHandlerName[];
 extern const char kCloudPrinterHandlerDescription[];
 
+extern const char kExperimentalAccessibilityFeaturesName[];
+extern const char kExperimentalAccessibilityFeaturesDescription[];
+
 extern const char kFCMInvalidationsName[];
 extern const char kFCMInvalidationsDescription[];
 
@@ -2036,9 +2039,6 @@
 extern const char kEolNotificationName[];
 extern const char kEolNotificationDescription[];
 
-extern const char kExperimentalAccessibilityFeaturesName[];
-extern const char kExperimentalAccessibilityFeaturesDescription[];
-
 extern const char kFileManagerTouchModeName[];
 extern const char kFileManagerTouchModeDescription[];