we must own/free the generator, even if we fail to return a cacherator

src/core/SkImageCacherator.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 "SkBitmap.h"
 #include "SkBitmapCache.h"
 #include "SkImageCacherator.h"
 #include "SkMallocPixelRef.h"
 #include "SkNextID.h"
 #include "SkPixelRef.h"
 
 #if SK_SUPPORT_GPU
 #include "GrContext.h"
 #include "GrGpuResourcePriv.h"
 #include "GrResourceKey.h"
 #include "GrTextureAccess.h"
 #include "GrYUVProvider.h"
 #include "SkGr.h"
 #include "SkGrPriv.h"
 #endif
 
 SkImageCacherator* SkImageCacherator::NewFromGenerator(SkImageGenerator* gen,
                                                        const SkIRect* subset) {
     if (!gen) {
         return nullptr;
     }
+
+    // We are required to take ownership of gen, regardless of if we return a cacherator or not
+    SkAutoTDelete<SkImageGenerator> genHolder(gen);
+
     const SkImageInfo& info = gen->getInfo();
     if (info.isEmpty()) {
         return nullptr;
     }
 
     uint32_t uniqueID = gen->uniqueID();
     const SkIRect bounds = SkIRect::MakeWH(info.width(), info.height());
     if (subset) {
         if (!bounds.contains(*subset)) {
             return nullptr;
         }
         if (*subset != bounds) {
             // we need a different uniqueID since we really are a subset of the raw generator
             uniqueID = SkNextID::ImageID();
         }
     } else {
         subset = &bounds;
     }
 
+    // Now that we know we can hand-off the generator (to be owned by the cacherator) we can
+    // release our holder. (we DONT want to delete it here anymore)

[tomhudson, 2015/09/14 16:58:16]

Nit: two words "any more" unless you're Edgar Allen Poe?
(And maybe an apostrophe in DONT)

+    genHolder.detach();
+
     return new SkImageCacherator(gen, gen->getInfo().makeWH(subset->width(), subset->height()),
                                  SkIPoint::Make(subset->x(), subset->y()), uniqueID);
 }
 
 SkImageCacherator::SkImageCacherator(SkImageGenerator* gen, const SkImageInfo& info,
                                      const SkIPoint& origin, uint32_t uniqueID)
     : fNotThreadSafeGenerator(gen)
     , fInfo(info)
     , fOrigin(origin)
     , fUniqueID(uniqueID)
@@ skipping 198 matching lines @@
     // 5. Ask the generator to return RGB(A) data, which the GPU can convert
     SkBitmap bitmap;
     if (this->generateBitmap(&bitmap)) {
         return GrRefCachedBitmapTexture(ctx, bitmap, usage);
     }
 #endif
 
     return nullptr;
 }