Stretching NativeViewHost, and misc tab capture fixes.

ui/views/controls/native/native_view_host_mac.h

 // 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.
 
 #ifndef UI_VIEWS_CONTROLS_NATIVE_NATIVE_VIEW_HOST_MAC_H_
 #define UI_VIEWS_CONTROLS_NATIVE_NATIVE_VIEW_HOST_MAC_H_
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/macros.h"
 #include "ui/views/controls/native/native_view_host_wrapper.h"
 #include "ui/views/views_export.h"
 
+@class NativeViewHostMacScalingView;
+
 namespace views {
 
 class NativeViewHost;
 
 // Mac implementation of NativeViewHostWrapper.
 class VIEWS_EXPORT NativeViewHostMac : public NativeViewHostWrapper {
  public:
   explicit NativeViewHostMac(NativeViewHost* host);
   ~NativeViewHostMac() override;
 
   // Overridden from NativeViewHostWrapper:
   void AttachNativeView() override;
   void NativeViewDetaching(bool destroyed) override;
   void AddedToWidget() override;
   void RemovedFromWidget() override;
   void InstallClip(int x, int y, int w, int h) override;
   bool HasInstalledClip() override;
   void UninstallClip() override;
-  void ShowWidget(int x, int y, int w, int h) override;
+  void ShowWidget(int x, int y, int w, int h, int render_w, int render_h)
+      override;
   void HideWidget() override;
   void SetFocus() override;
   gfx::NativeViewAccessible GetNativeViewAccessible() override;
   gfx::NativeCursor GetCursor(int x, int y) override;
 
  private:
   // Our associated NativeViewHost. Owns this.
   NativeViewHost* host_;
 
-  // Retain the native view as it may be destroyed at an unpredictable time.
-  base::scoped_nsobject<NSView> native_view_;
+  // Set when AttachNativeView() is called. This provides a scaling transform
+  // when ShowWidget() is called with a rendering size not equal to the region's
+  // size. When NativeViewDetaching() is called, this is destroyed.
+  base::scoped_nsobject<NativeViewHostMacScalingView> scaling_view_;
 
   DISALLOW_COPY_AND_ASSIGN(NativeViewHostMac);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_NATIVE_NATIVE_VIEW_HOST_AURA_H_