Add RenderDocument flag to about:flags

Bug: 936696
Change-Id: Iab187eafacbdb864bb2f26a6ff0a58b2f3589f99
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4607738
Reviewed-by: Fergal Daly <[email protected]>
Commit-Queue: Rakina Zata Amni <[email protected]>
Auto-Submit: Rakina Zata Amni <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1157423}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index 90c196d..c3f82061 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -2821,6 +2821,10 @@
 const char kPwaUpdateDialogForAppIconDescription[] =
     "Enable a confirmation dialog that shows up when a PWA changes its icon";
 
+const char kRenderDocumentName[] = "Enable RenderDocument";
+const char kRenderDocumentDescription[] =
+    "Enable swapping RenderFrameHosts on same-site navigations";
+
 const char kQuicName[] = "Experimental QUIC protocol";
 const char kQuicDescription[] = "Enable experimental QUIC protocol support.";