Added --deepColor option to SampleApp, triggers creation of a ten-bit/channel buffer on Windows.

src/views/ios/SkOSWindow_iOS.mm

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #import <UIKit/UIKit.h>
 #include "SkCanvas.h"
 #include "SkGraphics.h"
@@ skipping 41 matching lines @@
 void SkOSWindow::onAddMenu(const SkOSMenu* menu) {
     [(SkUIView*)fHWND onAddMenu:menu];
 }
 
 void SkOSWindow::onUpdateMenu(SkOSMenu* menu) {
     [(SkUIView*)fHWND onUpdateMenu:menu];
 }
 
 bool SkOSWindow::attach(SkBackEndTypes /* attachType */,
                         int /* msaaSampleCount */,
+                        bool /* deepColor */,
                         AttachmentInfo* info) {
     [(SkUIView*)fHWND getAttachmentInfo:info];
     bool success = true;
     return success;
 }
 
 void SkOSWindow::release() {}
 
 void SkOSWindow::present() {
 }