Prerender: Do not swap in prerendered page if current WebContents is being captured.

BUG=260350

Review URL: https://chromiumcodereview.appspot.com/19234002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@212738 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index 068f7c9..6e1065d 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -1077,6 +1077,10 @@
   }
 }
 
+int WebContentsImpl::GetCapturerCount() const {
+  return capturer_count_;
+}
+
 bool WebContentsImpl::IsCrashed() const {
   return (crashed_status_ == base::TERMINATION_STATUS_PROCESS_CRASHED ||
           crashed_status_ == base::TERMINATION_STATUS_ABNORMAL_TERMINATION ||