GM: replace boilerplate with macros

gm/imageblur.cpp

Index: gm/imageblur.cpp
diff --git a/gm/imageblur.cpp b/gm/imageblur.cpp
index f6ac0982b7762ba2e57a1f8eb00a608c7efd7871..575f02c095a0aacd4b98c954de0f58452c525e87 100644
--- a/gm/imageblur.cpp
+++ b/gm/imageblur.cpp
@@ -12,27 +12,7 @@
 #define WIDTH 500
 #define HEIGHT 500
 
-namespace skiagm {
-
-class ImageBlurGM : public GM {
-public:
-    ImageBlurGM(SkScalar sigmaX, SkScalar sigmaY, const char* suffix)
-        : fSigmaX(sigmaX), fSigmaY(sigmaY) {
-        this->setBGColor(0xFF000000);
-        fName.printf("imageblur%s", suffix);
-    }
-
-protected:
-
-    SkString onShortName() override {
-        return fName;
-    }
-
-    SkISize onISize() override {
-        return SkISize::Make(WIDTH, HEIGHT);
-    }
-
-    void onDraw(SkCanvas* canvas) override {
+void imageblurgm_draw(SkScalar fSigmaX, SkScalar fSigmaY, SkCanvas* canvas) {
         SkPaint paint;
         paint.setImageFilter(SkBlurImageFilter::Create(fSigmaX, fSigmaY))->unref();
         canvas->saveLayer(nullptr, &paint);
@@ -51,22 +31,10 @@ protected:
                              SkIntToScalar(y), textPaint);
         }
         canvas->restore();
-    }
-
-private:
-    SkScalar fSigmaX;
-    SkScalar fSigmaY;
-    SkString fName;
-
-    typedef GM INHERITED;
-};
-
-//////////////////////////////////////////////////////////////////////////////
-
-static GM* MyFactory1(void*) { return new ImageBlurGM(24.0f, 0.0f, ""); }
-static GMRegistry reg1(MyFactory1);
-
-static GM* MyFactory2(void*) { return new ImageBlurGM(80.0f, 80.0f, "_large"); }
-static GMRegistry reg2(MyFactory2);
-
+}
+DEF_SIMPLE_GM_BG(imageblur,       canvas, WIDTH, HEIGHT, SK_ColorBLACK) {
+    imageblurgm_draw(24.0f, 0.0f, canvas);
+}
+DEF_SIMPLE_GM_BG(imageblur_large, canvas, WIDTH, HEIGHT, SK_ColorBLACK) {
+    imageblurgm_draw(80.0f, 80.0f, canvas);
 }