Hide location bar on WebKit programmatic scroll.

content/common/view_messages.h

Index: content/common/view_messages.h
diff --git a/content/common/view_messages.h b/content/common/view_messages.h
index 4b5bb76f617a791b4db845a1545ca9aa77e1c879..fc55293d8c1f922e83e5ecdd2ef73761dab85229 100644
--- a/content/common/view_messages.h
+++ b/content/common/view_messages.h
@@ -1355,6 +1355,9 @@ IPC_MESSAGE_ROUTED1(ViewMsg_ImeBatchStateChanged,
 IPC_MESSAGE_ROUTED1(ViewMsg_EnableHidingTopControls,
                     bool /* enable */)
 
+// Tells the renderer to show or hide the top controls.
+IPC_MESSAGE_ROUTED1(ViewMsg_ShowTopControls, bool /* show */)
+
 IPC_MESSAGE_ROUTED0(ViewMsg_ShowImeIfNeeded)
 
 #elif defined(OS_MACOSX)
@@ -1489,6 +1492,10 @@ IPC_MESSAGE_ROUTED0(ViewHostMsg_UpdateScreenRects_ACK)
 IPC_MESSAGE_ROUTED1(ViewHostMsg_RequestMove,
                     gfx::Rect /* position */)
 
+// Sent by the renderer process to notify the browser that the web page has
+// hidden the URL bar programmatically by means of a scroll.
+IPC_MESSAGE_ROUTED1(ViewHostMsg_RequestShowTopControls, bool /* show */);
+
 // Notifies the browser that a frame in the view has changed. This message
 // has a lot of parameters and is packed/unpacked by functions defined in
 // render_messages.h.