[CUPS Printing] Add feature flag for PPD attribute support.

This might take more than milestone to finish so putting this behind a
feature flag.

Bug: 964919
Change-Id: I11acaa377b282d9acd9788b2e1a54bf0d2297511
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1617762
Commit-Queue: Vladislav Kuzkokov <[email protected]>
Reviewed-by: Lei Zhang <[email protected]>
Cr-Commit-Position: refs/heads/master@{#662221}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 4b79407..95350407 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -2918,6 +2918,11 @@
     "If Enabled, double tapping in webpages while in tablet mode will zoom the "
     "page.";
 
+const char kEnableAdvancedPpdAttributesName[] =
+    "Enables advanced PPD attributes";
+const char kEnableAdvancedPpdAttributesDescription[] =
+    "Enables advanced settings on CUPS printers";
+
 const char kEnableAppDataSearchName[] = "Enable app data search in launcher";
 const char kEnableAppDataSearchDescription[] =
     "Allow launcher search to access data available through Firebase App "