Browser Plugin: Simplify BrowserPluginGuestHelper

Since BrowserPlugin was first implemented, support for cross-process navigation
was dropped but BrowserPlugin*Helper classes maintain a lot of complexity that
was no longer necessary. This CL attempts to reduce some of this complexity
by simplifying BrowserPluginGuestHelper. It is only needed now to intercept
ViewHostMsg_* before arriving to RenderViewHost. It is still a separate class
because RenderViewHostObserver's lifetime is managed by RenderViewHost and
BrowserPluginGuest's lifetime is managed by WebContentsImpl.

This refactor/simplification is a prerequisite to introducing a
BrowserPluginGuestObserver class. Further changes will come in a subsequent
CL to simplify the message routing from

BrowserPluginEmbedderHelper --> BrowserPluginEmbedder --> BrowserPluginGuest

BUG=166165
Test=BrowserPluginHostTest.*

Review URL: https://codereview.chromium.org/11606005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@173804 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 8 insertions, 20 deletions

diff --git a/content/browser/browser_plugin/browser_plugin_guest_helper.h b/content/browser/browser_plugin/browser_plugin_guest_helper.h
index 0edac24..cb938c62 100644
--- a/content/browser/browser_plugin/browser_plugin_guest_helper.h
+++ b/content/browser/browser_plugin/browser_plugin_guest_helper.h
@@ -25,13 +25,12 @@ namespace content {
 class BrowserPluginGuest;
 class RenderViewHost;
 
-// Helper for browser plugin guest.
+// Helper for BrowserPluginGuest.
 //
-// It overrides different WebContents messages that require special treatment
-// for a WebContents to act as a guest. All functionality is handled by its
-// delegate. This class exists so we have separation of messages requiring
-// special handling, which can be moved to a message filter (IPC thread) for
-// future optimization.
+// The purpose of this class is to intercept messages from the guest RenderView
+// before they are handled by the standard message handlers in the browser
+// process. This permits overriding standard behavior with BrowserPlugin-
+// specific behavior.
 //
 // The lifetime of this class is managed by the associated RenderViewHost. A
 // BrowserPluginGuestHelper is created whenever a BrowserPluginGuest is created.
@@ -46,22 +45,11 @@ class BrowserPluginGuestHelper : public RenderViewHostObserver {
   virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE;
 
  private:
-  // Message handlers
-  void OnUpdateDragCursor(WebKit::WebDragOperation current_op);
-  void OnUpdateRect(const ViewHostMsg_UpdateRect_Params& params);
-  void OnHandleInputEventAck(WebKit::WebInputEvent::Type event_type,
-                             InputEventAckState ack_result);
-  void OnTakeFocus(bool reverse);
-  void OnShowWidget(int route_id, const gfx::Rect& initial_pos);
-  void OnMsgHasTouchEventHandlers(bool has_handlers);
-  void OnSetCursor(const WebCursor& cursor);
-#if defined(OS_MACOSX)
-  void OnShowPopup(const ViewHostMsg_ShowPopup_Params& params);
-#endif
+  // Returns whether a message should be forward to the helper's associated
+  // BrowserPluginGuest.
+  static bool ShouldForwardToBrowserPluginGuest(const IPC::Message& message);
 
   BrowserPluginGuest* guest_;
-  // A scoped container for notification registries.
-  NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(BrowserPluginGuestHelper);
 };