Remove work from constructors to facilitate debugging.

gm/composeshader.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 
 #include "SkBitmapProcShader.h"
@@ skipping 144 matching lines @@
     pts[0].set(0, 0);
     pts[1].set(SkIntToScalar(length), 0);
     colors[0] = SK_ColorBLUE;
     colors[1] = SkColorSetARGB(0, 0, 0, 0xFF);
     return SkGradientShader::CreateLinear(pts, colors, nullptr, 2, SkShader::kClamp_TileMode);
 }
 
 
 class ComposeShaderBitmapGM : public skiagm::GM {
 public:
-    ComposeShaderBitmapGM()
-        : fColorBitmapShader(nullptr)
-        , fAlpha8BitmapShader(nullptr)
-        , fLinearGradientShader(nullptr)
-    {
+    ComposeShaderBitmapGM() {}
+    ~ComposeShaderBitmapGM() {
+        SkSafeUnref(fColorBitmapShader);
+        SkSafeUnref(fAlpha8BitmapShader);
+        SkSafeUnref(fLinearGradientShader);
     }
 
+protected:
     void onOnceBeforeDraw() override {
         draw_color_bm(&fColorBitmap, squareLength);
         draw_alpha8_bm(&fAlpha8Bitmap, squareLength);
         SkMatrix s;
         s.reset();
         fColorBitmapShader = new SkBitmapProcShader(fColorBitmap, SkShader::kRepeat_TileMode,
                                                     SkShader::kRepeat_TileMode, &s);
         fAlpha8BitmapShader = new SkBitmapProcShader(fAlpha8Bitmap, SkShader::kRepeat_TileMode,
                                                      SkShader::kRepeat_TileMode, &s);
         fLinearGradientShader = make_linear_gradient_shader(squareLength);
     }
 
-    ~ComposeShaderBitmapGM() {
-        SkSafeUnref(fColorBitmapShader);
-        SkSafeUnref(fAlpha8BitmapShader);
-        SkSafeUnref(fLinearGradientShader);
-    }
-
-protected:
     SkString onShortName() override {
         return SkString("composeshader_bitmap");
     }
 
     SkISize onISize() override {
         return SkISize::Make(7 * (squareLength + 5), 2 * (squareLength + 5));
     }
 
     void onDraw(SkCanvas* canvas) override {
         SkAutoTUnref<SkXfermode> xfer(SkXfermode::Create(SkXfermode::kDstOver_Mode));
@@ skipping 22 matching lines @@
                 paint.setAlpha(alpha);
                 paint.setShader(shader);
                 canvas->drawRect(r, paint);
 
                 canvas->translate(r.width() + 5, 0);
             }
             canvas->restore();
             canvas->translate(0, r.height() + 5);
         }
     }
+    
 private:
     /** This determines the length and width of the bitmaps used in the SkComposeShaders.  Values
      *  above 20 may cause an SkASSERT to fail in SkSmallAllocator. However, larger values will
      *  work in a release build.  You can change this parameter and then compile a release build
      *  to have this GM draw larger bitmaps for easier visual inspection.
      */
     static const int squareLength = 20;
 
     SkBitmap fColorBitmap;
     SkBitmap fAlpha8Bitmap;
-    SkShader* fColorBitmapShader;
-    SkShader* fAlpha8BitmapShader;
-    SkShader* fLinearGradientShader;
+    SkShader* fColorBitmapShader{nullptr};
+    SkShader* fAlpha8BitmapShader{nullptr};
+    SkShader* fLinearGradientShader{nullptr};
 
     typedef GM INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 DEF_GM( return new ComposeShaderGM; )
 DEF_GM( return new ComposeShaderAlphaGM; )
 DEF_GM( return new ComposeShaderBitmapGM; )