views: Factor out SingleSplitView Observer into SingleSplitViewListener.

chrome/browser/ui/views/frame/browser_view.cc

Index: chrome/browser/ui/views/frame/browser_view.cc
diff --git a/chrome/browser/ui/views/frame/browser_view.cc b/chrome/browser/ui/views/frame/browser_view.cc
index 09484bc25491e5aaaaa349053597c2bb8bb52af2..586e8c911786aaddf2acfc375229c9bc11d5bcc0 100644
--- a/chrome/browser/ui/views/frame/browser_view.cc
+++ b/chrome/browser/ui/views/frame/browser_view.cc
@@ -1830,9 +1830,9 @@ bool BrowserView::DrawInfoBarArrows(int* x) const {
   return true;
 }
 
-bool BrowserView::SplitHandleMoved(views::SingleSplitView* view) {
-  for (int i = 0; i < view->child_count(); ++i)
-    view->child_at(i)->InvalidateLayout();
+bool BrowserView::SplitHandleMoved(views::SingleSplitView* sender) {
+  for (int i = 0; i < sender->child_count(); ++i)
+    sender->child_at(i)->InvalidateLayout();
   SchedulePaint();
   Layout();
   return false;