retool image cache to be generic cache

src/lazy/SkCachingPixelRef.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 "SkCachingPixelRef.h"
 #include "SkBitmapCache.h"
 
@@ skipping 12 matching lines @@
     dst->setPixelRef(ref);
     return true;
 }
 
 SkCachingPixelRef::SkCachingPixelRef(const SkImageInfo& info,
                                      SkImageGenerator* generator,
                                      size_t rowBytes)
     : INHERITED(info)
     , fImageGenerator(generator)
     , fErrorInDecoding(false)
-    , fScaledCacheId(NULL)
     , fRowBytes(rowBytes) {
     SkASSERT(fImageGenerator != NULL);
 }
 SkCachingPixelRef::~SkCachingPixelRef() {
     SkDELETE(fImageGenerator);
-    SkASSERT(NULL == fScaledCacheId);
     // Assert always unlock before unref.
 }
 
 bool SkCachingPixelRef::onNewLockPixels(LockRec* rec) {
     if (fErrorInDecoding) {
         return false;  // don't try again.
     }
 
     const SkImageInfo& info = this->info();
-    SkBitmap bitmap;
-    SkASSERT(NULL == fScaledCacheId);
-    fScaledCacheId = SkBitmapCache::FindAndLock(this->getGenerationID(), info.fWidth, info.fHeight,
-                                                &bitmap);
-    if (NULL == fScaledCacheId) {
+    if (!SkBitmapCache::Find(this->getGenerationID(), info.fWidth, info.fHeight, &fLockedBitmap)) {
         // Cache has been purged, must re-decode.
-        if (!bitmap.allocPixels(info, fRowBytes)) {
+        if (!fLockedBitmap.allocPixels(info, fRowBytes)) {
             fErrorInDecoding = true;
             return false;
         }
-        SkAutoLockPixels autoLockPixels(bitmap);
-        if (!fImageGenerator->getPixels(info, bitmap.getPixels(), fRowBytes)) {
+        if (!fImageGenerator->getPixels(info, fLockedBitmap.getPixels(), fRowBytes)) {
             fErrorInDecoding = true;
             return false;
         }
-        fScaledCacheId = SkBitmapCache::AddAndLock(this->getGenerationID(),
-                                                   info.fWidth, info.fHeight, bitmap);
-        SkASSERT(fScaledCacheId != NULL);
+        SkBitmapCache::Add(this->getGenerationID(), info.fWidth, info.fHeight, fLockedBitmap);
     }
 
-    // Now bitmap should contain a concrete PixelRef of the decoded
-    // image.
-    SkAutoLockPixels autoLockPixels(bitmap);
-    void* pixels = bitmap.getPixels();
+    // Now bitmap should contain a concrete PixelRef of the decoded image.
+    void* pixels = fLockedBitmap.getPixels();
     SkASSERT(pixels != NULL);
-
-    // At this point, the autoLockPixels will unlockPixels()
-    // to remove bitmap's lock on the pixels.  We will then
-    // destroy bitmap.  The *only* guarantee that this pointer
-    // remains valid is the guarantee made by
-    // SkScaledImageCache that it will not destroy the *other*
-    // bitmap (SkScaledImageCache::Rec.fBitmap) that holds a
-    // reference to the concrete PixelRef while this record is
-    // locked.
     rec->fPixels = pixels;
     rec->fColorTable = NULL;
-    rec->fRowBytes = bitmap.rowBytes();
+    rec->fRowBytes = fLockedBitmap.rowBytes();
     return true;
 }
 
 void SkCachingPixelRef::onUnlockPixels() {
-    SkASSERT(fScaledCacheId != NULL);
-    SkScaledImageCache::Unlock( static_cast<SkScaledImageCache::ID*>(fScaledCacheId));
-    fScaledCacheId = NULL;
+    fLockedBitmap.reset();
 }