Address memory leak in SkScaledImageCache

src/core/SkScaledImageCache.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkScaledImageCache.h"
 #include "SkMipMap.h"
 #include "SkOnce.h"
@@ skipping 410 matching lines @@
 
 
 ////////////////////////////////////////////////////////////////////////////////
 /**
    This private method is the fully general record adder. All other
    record adders should call this funtion. */
 SkScaledImageCache::ID* SkScaledImageCache::addAndLock(SkScaledImageCache::Rec* rec) {
     SkASSERT(rec);
     // See if we already have this key (racy inserts, etc.)
     Rec* existing = this->findAndLock(rec->fKey);
-    if (existing != NULL) {
+    if (NULL != existing) {
+        // Since we already have a matching entry, just delete the new one and return.
+        // Call sites cannot assume the passed in object will live past this call.
+        SkDELETE(rec);
         return rec_to_id(existing);
     }
 
     this->addToHead(rec);
     SkASSERT(1 == rec->fLockCount);
 #ifdef USE_HASH
     SkASSERT(fHash);
     fHash->add(rec);
 #endif
     // We may (now) be overbudget, so see if we need to purge something.
@@ skipping 348 matching lines @@
     return SkScaledImageCache::GetBytesUsed();
 }
 
 size_t SkGraphics::GetImageCacheByteLimit() {
     return SkScaledImageCache::GetByteLimit();
 }
 
 size_t SkGraphics::SetImageCacheByteLimit(size_t newLimit) {
     return SkScaledImageCache::SetByteLimit(newLimit);
 }