Revert "Revert of remove unused SkCachingPixelRef (patchset #1 id:1 of https://codereview.chromium.…

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"
-#include "SkRect.h"
-
-bool SkCachingPixelRef::Install(SkImageGenerator* generator,
-                                SkBitmap* dst) {
-    SkASSERT(dst != nullptr);
-    if (nullptr == generator) {
-        return false;
-    }
-    const SkImageInfo info = generator->getInfo();
-    if (!dst->setInfo(info)) {
-        delete generator;
-        return false;
-    }
-    SkAutoTUnref<SkCachingPixelRef> ref(new SkCachingPixelRef(info, generator, dst->rowBytes()));
-    dst->setPixelRef(ref);
-    return true;
-}
-
-SkCachingPixelRef::SkCachingPixelRef(const SkImageInfo& info,
-                                     SkImageGenerator* generator,
-                                     size_t rowBytes)
-    : INHERITED(info)
-    , fImageGenerator(generator)
-    , fErrorInDecoding(false)
-    , fRowBytes(rowBytes) {
-    SkASSERT(fImageGenerator != nullptr);
-}
-SkCachingPixelRef::~SkCachingPixelRef() {
-    delete fImageGenerator;
-    // Assert always unlock before unref.
-}
-
-bool SkCachingPixelRef::onNewLockPixels(LockRec* rec) {
-    if (fErrorInDecoding) {
-        return false;  // don't try again.
-    }
-
-    const SkImageInfo& info = this->info();
-    if (!SkBitmapCache::Find(
-                this->getGenerationID(), info.bounds(), &fLockedBitmap)) {
-        // Cache has been purged, must re-decode.
-        if (!fLockedBitmap.tryAllocPixels(info, fRowBytes)) {
-            fErrorInDecoding = true;
-            return false;
-        }
-        if (!fImageGenerator->getPixels(info, fLockedBitmap.getPixels(), fRowBytes)) {
-            fErrorInDecoding = true;
-            return false;
-        }
-        fLockedBitmap.setImmutable();
-        SkBitmapCache::Add(this, info.bounds(), fLockedBitmap);
-    }
-
-    // Now bitmap should contain a concrete PixelRef of the decoded image.
-    void* pixels = fLockedBitmap.getPixels();
-    SkASSERT(pixels != nullptr);
-    rec->fPixels = pixels;
-    rec->fColorTable = nullptr;
-    rec->fRowBytes = fLockedBitmap.rowBytes();
-    return true;
-}
-
-void SkCachingPixelRef::onUnlockPixels() {
-    fLockedBitmap.reset();
-}