Add user visible flag for WebContentsOcclusion on Windows.

Bug: 813093
Change-Id: I8e4779551cb75d88f1f07c069cd7e5d7793da5b1
Reviewed-on: https://chromium-review.googlesource.com/c/1455094
Commit-Queue: David Bienvenu <[email protected]>
Reviewed-by: Elly Fong-Jones <[email protected]>
Reviewed-by: François Doray <[email protected]>
Cr-Commit-Position: refs/heads/master@{#630102}
diff --git a/chrome/browser/flag_descriptions.h b/chrome/browser/flag_descriptions.h
index 2de65a6..3671fca 100644
--- a/chrome/browser/flag_descriptions.h
+++ b/chrome/browser/flag_descriptions.h
@@ -2201,6 +2201,13 @@
 
 #endif  // defined(OS_MACOSX) || defined(OS_CHROMEOS)
 
+#if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_CHROMEOS)
+
+extern const char kWebContentsOcclusionName[];
+extern const char kWebContentsOcclusionDescription[];
+
+#endif  // defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_CHROMEOS)
+
 // Feature flags --------------------------------------------------------------
 
 #if defined(DCHECK_IS_CONFIGURABLE)