Remove caching from the draw-atlas GMs. Fixes bugs cycling backends.

gm/drawatlas.cpp

 /*
  * Copyright 2015 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 "SkCanvas.h"
 #include "SkRSXform.h"
@@ skipping 17 matching lines @@
         r.inset(-1, -1);
         // zero out a place (with a 1-pixel border) to land our drawing.
         canvas->drawRect(r, paint);
         paint.setXfermode(nullptr);
         paint.setColor(SK_ColorBLUE);
         paint.setAntiAlias(true);
         canvas->drawOval(target, paint);
         return surface->makeImageSnapshot();
     }
 
-    sk_sp<SkImage> fAtlas;
-
 public:
     DrawAtlasGM() {}
 
 protected:
 
     SkString onShortName() override {
         return SkString("draw-atlas");
     }
 
     SkISize onISize() override {
         return SkISize::Make(640, 480);
     }
 
     void onDraw(SkCanvas* canvas) override {
         const SkRect target = { 50, 50, 80, 90 };
-        if (nullptr == fAtlas) {
-            fAtlas = MakeAtlas(canvas, target);
-        }
+        auto atlas = MakeAtlas(canvas, target);
 
         const struct {
             SkScalar fScale;
             SkScalar fDegrees;
             SkScalar fTx;
             SkScalar fTy;
 
             void apply(SkRSXform* xform) const {
                 const SkScalar rad = SkDegreesToRadians(fDegrees);
                 xform->fSCos = fScale * SkScalarCos(rad);
@@ skipping 16 matching lines @@
         for (int i = 0; i < N; ++i) {
             rec[i].apply(&xform[i]);
             tex[i] = target;
             colors[i] = 0x80FF0000 + (i * 40 * 256);
         }
 
         SkPaint paint;
         paint.setFilterQuality(kLow_SkFilterQuality);
         paint.setAntiAlias(true);
 
-        canvas->drawAtlas(fAtlas.get(), xform, tex, N, nullptr, &paint);
+        canvas->drawAtlas(atlas.get(), xform, tex, N, nullptr, &paint);
         canvas->translate(0, 100);
-        canvas->drawAtlas(fAtlas.get(), xform, tex, colors, N, SkXfermode::kSrcIn_Mode, nullptr, &paint);
+        canvas->drawAtlas(atlas.get(), xform, tex, colors, N, SkXfermode::kSrcIn_Mode, nullptr, &paint);
     }
 
 private:
     typedef GM INHERITED;
 };
 DEF_GM( return new DrawAtlasGM; )
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 #include "SkPath.h"
 #include "SkPathMeasure.h"
@@ skipping 58 matching lines @@
     SkPath path;
     path.addOval(SkRect::MakeXYWH(160, 160, 540, 540));
 
     draw_text_on_path_rigid(canvas, text0, N, pos, path, paint);
 
     paint.setStyle(SkPaint::kStroke_Style);
     canvas->drawPath(path, paint);
 }