If Ashmem cache fails pinCache, do not reallocate.

src/lazy/SkLruImageCache.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 "SkLruImageCache.h"
 
 static intptr_t NextGenerationID() {
@@ skipping 113 matching lines @@
 void SkLruImageCache::releaseCache(intptr_t ID) {
     SkASSERT(ID != SkImageCache::UNINITIALIZED_ID);
     SkAutoMutexAcquire ac(&fMutex);
     CachedPixels* pixels = this->findByID(ID);
     SkASSERT(pixels != NULL);
     pixels->unlock();
     this->purgeIfNeeded();
 }
 
 void SkLruImageCache::throwAwayCache(intptr_t ID) {
-    SkASSERT(ID != SkImageCache::UNINITIALIZED_ID);
     SkAutoMutexAcquire ac(&fMutex);
     CachedPixels* pixels = this->findByID(ID);
     if (pixels != NULL) {
         if (pixels->isLocked()) {
             pixels->unlock();
         }
         this->removePixels(pixels);
     }
 }
 
 void SkLruImageCache::removePixels(CachedPixels* pixels) {
     // Mutex is already locked.
     SkASSERT(!pixels->isLocked());
     const size_t size = pixels->getLength();
     SkASSERT(size <= fRamUsed);
     fLRU.remove(pixels);
     SkDELETE(pixels);
     fRamUsed -= size;
 }
 
 CachedPixels* SkLruImageCache::findByID(intptr_t ID) const {
     // Mutex is already locked.
+    if (SkImageCache::UNINITIALIZED_ID == ID) {
+        return NULL;
+    }
     Iter iter;
     // Start from the head, most recently used.
     CachedPixels* pixels = iter.init(fLRU, Iter::kHead_IterStart);
     while (pixels != NULL) {
         if (pixels->getID() == ID) {
             return pixels;
         }
         pixels = iter.next();
     }
     return NULL;
@@ skipping 12 matching lines @@
         CachedPixels* pixels = iter.init(fLRU, Iter::kTail_IterStart);
         while (pixels != NULL && fRamUsed > limit) {
             CachedPixels* prev = iter.prev();
             if (!pixels->isLocked()) {
                 this->removePixels(pixels);
             }
             pixels = prev;
         }
     }
 }