Fix crashes due to gfx::Image unsafe thread passing

gfx::Image has |storage_| member which is base::RefCounted, not thread
safe. Thus passing around gfx::Image to other threads by copying is
incorrect.

Workaround by using scoped_ptr and making ImageRecord class
RefCountedThreadSafe.

Related discussion:
https://groups.google.com/a/chromium.org/forum/#!topic/chromium-dev/8LqVoXQ_2bo

BUG=471800

Review URL: https://codereview.chromium.org/1031293002

Cr-Commit-Position: refs/heads/master@{#323720}

1 files changed, 3 insertions, 2 deletions

diff --git a/components/enhanced_bookmarks/persistent_image_store.h b/components/enhanced_bookmarks/persistent_image_store.h
index 5a0c41d..d6f12f35 100644
--- a/components/enhanced_bookmarks/persistent_image_store.h
+++ b/components/enhanced_bookmarks/persistent_image_store.h
@@ -20,9 +20,10 @@ class PersistentImageStore : public ImageStore {
   explicit PersistentImageStore(const base::FilePath& path);
   bool HasKey(const GURL& page_url) override;
   void Insert(const GURL& page_url,
-              const enhanced_bookmarks::ImageRecord& image) override;
+              scoped_refptr<enhanced_bookmarks::ImageRecord> image) override;
   void Erase(const GURL& page_url) override;
-  enhanced_bookmarks::ImageRecord Get(const GURL& page_url) override;
+  scoped_refptr<enhanced_bookmarks::ImageRecord> Get(
+      const GURL& page_url) override;
   gfx::Size GetSize(const GURL& page_url) override;
   void GetAllPageUrls(std::set<GURL>* urls) override;
   void ClearAll() override;