Add samples to Viewer.

tools/viewer/Slide.h

Index: tools/viewer/Slide.h
diff --git a/tools/viewer/Slide.h b/tools/viewer/Slide.h
index cdc225b0a8c24b74762d075d6a4f6b21a1353909..bc0ffd40168f900fee49fa847cc6b699878f246e 100644
--- a/tools/viewer/Slide.h
+++ b/tools/viewer/Slide.h
@@ -19,11 +19,13 @@ class Slide : public SkRefCnt {
 public:
     virtual ~Slide() {}
 
-    virtual SkISize getDimensions() const = 0;
+    virtual SkISize getDimensions() const {
+        return SkISize::Make(0, 0);
+    }
 
     virtual void draw(SkCanvas* canvas) = 0;
     virtual bool animate(const SkAnimTimer&) { return false;  }
-    virtual void load() {}
+    virtual void load(SkScalar winWidth, SkScalar winHeight) {}
     virtual void unload() {}
 
     SkString getName() { return fName; }