arc: Add a flag for keyboard shortcut helper integration

This CL adds a feature flag for Keyboard Shortcut Helper integration.

Design doc: http://go/arc-keyboard-shortcut-helper

TEST=adb shell getprop ro.boot.keyboard_shortcut_helper_integration
BUG=b:148178557

Change-Id: I8eb2ca847fee41c9ca6a1871631962b441d818a3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3010907
Reviewed-by: Yuichiro Hanada <[email protected]>
Commit-Queue: Tetsui Ohkubo <[email protected]>
Cr-Commit-Position: refs/heads/master@{#899164}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 35157b1..c49aaaa 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -4001,6 +4001,11 @@
     "Allows pasting of images to Android apps through commitContent API and "
     "share intent.";
 
+const char kArcKeyboardShortcutHelperIntegrationName[] =
+    "Enable keyboard shortcut helper integration for ARC";
+const char kArcKeyboardShortcutHelperIntegrationDescription[] =
+    "Shows keyboard shortcuts from Android apps in Chrome OS Shortcut Viewer";
+
 const char kArcNativeBridgeToggleName[] =
     "Toggle between native bridge implementations for ARC";
 const char kArcNativeBridgeToggleDescription[] =