Use Windowing system-specific WindowContext factories.

tools/viewer/sk_app/mac/Window_mac.cpp

 /*
 * Copyright 2016 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */
 
 //#include <tchar.h>
 
 #include "SkUtils.h"
 #include "Timer.h"
-#include "../GLWindowContext.h"
+#include "WindowContextFactory_mac.h"
 #include "Window_mac.h"
 
 namespace sk_app {
 
 Window* Window::CreateNativeWindow(void* platformData) {
 #if 0
     // TODO: platform-specific window creation
     Display* display = (Display*)platformData;
 
     Window_mac* window = new Window_mac();
@@ skipping 240 matching lines @@
     XSetWMName(fDisplay, fWindow, &textproperty);    
 }
 
 void Window_mac::show() {
     XMapWindow(fDisplay, fWindow);
 }
 
 bool Window_mac::attach(BackendType attachType, const DisplayParams& params) {
     this->initWindow(fDisplay, &params);
 
-    ContextPlatformData_mac platformData;
-    platformData.fDisplay = fDisplay;
-    platformData.fWindow = fWindow;
-    platformData.fVisualInfo = fVisualInfo;
+    MacWindowInfo info;
+#if 0
+    // Init Mac window info here
+    info.foo = foo;
+#endif
     switch (attachType) {
 #ifdef SK_VULKAN
         case kVulkan_BackendType:
-            fWindowContext = VulkanWindowContext::Create((void*)&platformData, params);
+            fWindowContext = NewVulkanForMac(info, params);
             break;
 #endif
         case kNativeGL_BackendType:
         default:
-            fWindowContext = GLWindowContext::Create((void*)&platformData, params);
+            fWindowContext = NewGLForMac(info, params);
             break;
     }
 
     return (SkToBool(fWindowContext));
 }
 
 void Window_mac::onInval() {
     XEvent event;
     event.type = Expose;
     event.xexpose.send_event = True;
     event.xexpose.display = fDisplay;
     event.xexpose.window = fWindow;
     event.xexpose.x = 0;
     event.xexpose.y = 0;
     event.xexpose.width = fWidth;
     event.xexpose.height = fHeight;
     event.xexpose.count = 0;
     
     XSendEvent(fDisplay, fWindow, False, 0, &event);
 }
 #endif
     
 }   // namespace sk_app