notification balloons: Remove views and cocoa implementations of BalloonCollection.

chrome/browser/ui/cocoa/notifications/balloon_view_host_mac.mm

-// Copyright (c) 2012 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 "chrome/browser/ui/cocoa/notifications/balloon_view_host_mac.h"
-
-#import <Cocoa/Cocoa.h>
-
-#include "content/public/browser/render_view_host.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/browser/web_contents_view.h"
-
-BalloonViewHost::BalloonViewHost(Balloon* balloon)
-    : BalloonHost(balloon) {
-}
-
-BalloonViewHost::~BalloonViewHost() {
-   Shutdown();
-}
-
-void BalloonViewHost::UpdateActualSize(const gfx::Size& new_size) {
-  // Update the size of the web contents view.
-  // The view's new top left corner should be identical to the view's old top
-  // left corner.
-  NSView* web_contents_view = web_contents_->GetView()->GetNativeView();
-  NSRect old_wcv_frame = [web_contents_view frame];
-  CGFloat new_x = old_wcv_frame.origin.x;
-  CGFloat new_y =
-      old_wcv_frame.origin.y + (old_wcv_frame.size.height - new_size.height());
-  NSRect new_wcv_frame =
-      NSMakeRect(new_x, new_y, new_size.width(), new_size.height());
-  [web_contents_view setFrame:new_wcv_frame];
-
-  // Update the size of the balloon view.
-  NSView* view = native_view();
-  NSRect frame = [view frame];
-  frame.size.width = new_size.width();
-  frame.size.height = new_size.height();
-
-  [view setFrame:frame];
-  [view setNeedsDisplay:YES];
-}
-
-gfx::NativeView BalloonViewHost::native_view() const {
-  return web_contents_->GetView()->GetContentNativeView();
-}