Rename VulkanViewer to Viewer, take 2.

tools/vulkan/viewer/SKPSlide.h

-/*
-* Copyright 2016 Google Inc.
-*
-* Use of this source code is governed by a BSD-style license that can be
-* found in the LICENSE file.
-*/
-
-#ifndef SKPSlide_DEFINED
-#define SKPSlide_DEFINED
-
-#include "Slide.h"
-#include "SkPicture.h"
-
-class SKPSlide : public Slide {
-public:
-    SKPSlide(const SkString& name, const SkString& path);
-    ~SKPSlide() override;
-
-    SkISize getDimensions() const override { return fCullRect.size(); }
-
-    void draw(SkCanvas* canvas) override;
-    void load() override;
-    void unload() override;
-
-private:
-    SkString               fPath;
-    sk_sp<const SkPicture> fPic;
-    SkIRect                fCullRect;
-};
-
-#endif