Minor code cleanup (left over from prior CL)

gm/imagefiltersscaled.cpp

Index: gm/imagefiltersscaled.cpp
diff --git a/gm/imagefiltersscaled.cpp b/gm/imagefiltersscaled.cpp
index b53263606c978b9e2ae3f1dbd348e96f0f6591be..e98749ebac3bd18ac561b4823e1b8fe252e4f8f9 100644
--- a/gm/imagefiltersscaled.cpp
+++ b/gm/imagefiltersscaled.cpp
@@ -27,21 +27,21 @@ namespace skiagm {
 
 class ImageFiltersScaledGM : public GM {
 public:
-    ImageFiltersScaledGM() : fInitialized(false) {
+    ImageFiltersScaledGM() {
         this->setBGColor(0x00000000);
     }
 
 protected:
 
-    virtual SkString onShortName() {
+    SkString onShortName() override {
         return SkString("imagefiltersscaled");
     }
 
-    virtual SkISize onISize() {
+    SkISize onISize() override {
         return SkISize::Make(1428, 500);
     }
 
-    void make_gradient_circle(int width, int height) {
+    void makeGradientCircle(int width, int height) {
         SkScalar x = SkIntToScalar(width / 2);
         SkScalar y = SkIntToScalar(height / 2);
         SkScalar radius = SkScalarMul(SkMinScalar(x, y), SkIntToScalar(4) / SkIntToScalar(5));
@@ -60,15 +60,13 @@ protected:
         canvas.drawCircle(x, y, radius, paint);
     }
 
-    virtual void onDraw(SkCanvas* canvas) {
-        if (!fInitialized) {
-            fCheckerboard.allocN32Pixels(64, 64);
-            SkCanvas checkerboardCanvas(fCheckerboard);
-            sk_tool_utils::draw_checkerboard(&checkerboardCanvas, 0xFFA0A0A0, 0xFF404040, 8);
+    void onOnceBeforeDraw() override {
+        fCheckerboard = sk_tool_utils::create_checkerboard_bitmap(64, 64,
+                                                                  0xFFA0A0A0, 0xFF404040, 8);
+        this->makeGradientCircle(64, 64);
+    }
 
-            this->make_gradient_circle(64, 64);
-            fInitialized = true;
-        }
+    void onDraw(SkCanvas* canvas) override {
         canvas->clear(SK_ColorBLACK);
 
         SkAutoTUnref<SkImageFilter> gradient(SkBitmapSource::Create(fGradientCircle));
@@ -152,15 +150,13 @@ protected:
     }
 
 private:
-    bool fInitialized;
     SkBitmap fCheckerboard;
     SkBitmap fGradientCircle;
+
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
-static GM* MyFactory(void*) { return new ImageFiltersScaledGM; }
-static GMRegistry reg(MyFactory);
-
+DEF_GM(return new ImageFiltersScaledGM;)
 }