First pass at VulkanViewer

tools/vulkan/Window.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 "Window.h"
+
+#include "SkSurface.h"
+#include "SkCanvas.h"
+#include "VulkanTestContext.h"
+
+static bool default_key_func(int key, bool down, void* userData) {
+    return false;
+}
+
+static bool default_mouse_func(int x, int y, bool down, void* userData) {
+    return false;
+}
+
+static void default_paint_func(SkCanvas*, void* userData) {}
+
+Window::Window() : fKeyFunc(default_key_func)
+                 , fMouseFunc(default_mouse_func)
+                 , fPaintFunc(default_paint_func) {
+}
+
+void Window::detach() {
+    delete fTestContext;
+    fTestContext = nullptr;
+}
+
+void Window::onPaint() {
+    SkSurface* backbuffer = fTestContext->getBackbufferSurface();
+    if (backbuffer) {
+        // draw into the canvas of this surface
+        SkCanvas* canvas = backbuffer->getCanvas();
+
+        fPaintFunc(canvas, fPaintUserData);
+
+        canvas->flush();
+
+        fTestContext->swapBuffers();
+    }
+
+}
+
+
+void Window::onSize() {
+    fTestContext->resize();
+}