Use RefCountedThreadSafe in GPU IDC

cc/tiles/gpu_image_decode_cache.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_TILES_GPU_IMAGE_DECODE_CACHE_H_
 #define CC_TILES_GPU_IMAGE_DECODE_CACHE_H_
 
 #include <memory>
 #include <unordered_map>
 #include <vector>
@@ skipping 212 matching lines @@
       int ref_reached_zero_count = 0;
     };
 
     void ReportUsageStats() const;
 
     // May be null if image not yet uploaded / prepared.
     sk_sp<SkImage> image_;
     UsageStats usage_stats_;
   };
 
-  struct ImageData : public base::RefCounted<ImageData> {
+  struct ImageData : public base::RefCountedThreadSafe<ImageData> {
     ImageData(DecodedDataMode mode,
               size_t size,
               const gfx::ColorSpace& target_color_space,
               const SkImage::DeferredTextureImageUsageParams& upload_params);
 
     const DecodedDataMode mode;
     const size_t size;
     gfx::ColorSpace target_color_space;
     bool is_at_raster = false;
     SkImage::DeferredTextureImageUsageParams upload_params;
 
     // If true, this image is no longer in our |persistent_cache_| and will be
     // deleted as soon as its ref count reaches zero.
     bool is_orphaned = false;
 
     DecodedImageData decode;
     UploadedImageData upload;
 
    private:
-    friend class base::RefCounted<ImageData>;
+    friend class base::RefCountedThreadSafe<ImageData>;
     ~ImageData();
   };
 
   // A ref-count and ImageData, used to associate the ImageData with a specific
   // DrawImage in the |in_use_cache_|.
   struct InUseCacheEntry {
     explicit InUseCacheEntry(scoped_refptr<ImageData> image_data);
     InUseCacheEntry(const InUseCacheEntry& other);
     InUseCacheEntry(InUseCacheEntry&& other);
     ~InUseCacheEntry();
@@ skipping 104 matching lines @@
 
   // We can't release GPU backed SkImages without holding the context lock,
   // so we add them to this list and defer deletion until the next time the lock
   // is held.
   std::vector<sk_sp<SkImage>> images_pending_deletion_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TILES_GPU_IMAGE_DECODE_CACHE_H_