Add ctrl+mousewheel plumbing to MimeHandlerView.

extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest.h"
 
 #include "base/strings/stringprintf.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/common/url_constants.h"
@@ skipping 100 matching lines @@
       content::Referrer(),
       ui::PAGE_TRANSITION_AUTO_TOPLEVEL,
       std::string());
 }
 
 void MimeHandlerViewGuest::DidInitialize() {
   if (delegate_)
     delegate_->AttachHelpers();
 }
 
+void MimeHandlerViewGuest::ContentsZoomChange(bool zoom_in) {
+  if (delegate_)
+    delegate_->ChangeZoom(zoom_in);
+}
+
 void MimeHandlerViewGuest::HandleKeyboardEvent(
     WebContents* source,
     const content::NativeWebKeyboardEvent& event) {
   if (!attached())
     return;
 
   // Send the keyboard events back to the embedder to reprocess them.
   // TODO(fsamuel): This introduces the possibility of out-of-order keyboard
   // events because the guest may be arbitrarily delayed when responding to
   // keyboard events. In that time, the embedder may have received and processed
   // additional key events. This needs to be fixed as soon as possible.
   // See http://crbug.com/229882.
   embedder_web_contents()->GetDelegate()->HandleKeyboardEvent(web_contents(),
                                                               event);
 }
 
 }  // namespace extensions