Minor code cleanup (left over from prior CL)

gm/imagefiltersclipped.cpp

Index: gm/imagefiltersclipped.cpp
diff --git a/gm/imagefiltersclipped.cpp b/gm/imagefiltersclipped.cpp
index 362d327b37cf4548cba1a684fa5f65179576f38e..bf651a831ea644ac3b5c845e969f87227d5e10dc 100644
--- a/gm/imagefiltersclipped.cpp
+++ b/gm/imagefiltersclipped.cpp
@@ -28,12 +28,11 @@ namespace skiagm {
 
 class ImageFiltersClippedGM : public GM {
 public:
-    ImageFiltersClippedGM() : fInitialized(false) {
+    ImageFiltersClippedGM() {
         this->setBGColor(0x00000000);
     }
 
 protected:
-
     SkString onShortName() override {
         return SkString("imagefiltersclipped");
     }
@@ -42,7 +41,7 @@ protected:
         return SkISize::Make(860, 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 = SkMinScalar(x, y) * 0.8f;
@@ -80,15 +79,13 @@ protected:
         canvas->restore();
     }
 
-    void onDraw(SkCanvas* canvas) override {
-        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));
@@ -150,15 +147,13 @@ protected:
     }
 
 private:
-    bool fInitialized;
     SkBitmap fCheckerboard;
     SkBitmap fGradientCircle;
+
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
-static GM* MyFactory(void*) { return new ImageFiltersClippedGM; }
-static GMRegistry reg(MyFactory);
-
+DEF_GM(return new ImageFiltersClippedGM;)
 }