History: Modify about:flags description for experimental full history sync feature.

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 7613848a19cd5476468c03b2aafd62d06f7c66d1..6f4a96e711552107e483d4d7b315a9fb9c8410af 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -7019,7 +7019,7 @@ Keep your key file in a safe place. You will need it to create new versions of y
         Enable full history sync.
       </message>
       <message name="IDS_FLAGS_FULL_HISTORY_SYNC_DESCRIPTION" desc="Description for the flag to enable full history sync.">
-        Sync all visits (not just typed URLs) when signed in to a Google Account.
+        If tab sync is enabled, this feature allows you to see and delete history entries from your synced devices at chrome://history.
       </message>
       <message name="IDS_FLAGS_OLD_CHECKBOX_STYLE_DESCRIPTION" desc="Description of the flag to turn off the new checkbox style.">
         Disables new appearance and sizing behavior for checkboxes and radio buttons.