Web Locks: Make LockManager non-refcounted

The manager had only a single owner (StoragePartitionImpl) so there
was no reason it needed to be refcounted. Change ownership to be
unique_ptr.

Change-Id: Iea1895ecc41cb9614ef0f5624a6b0cfbc037e6bb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2028121
Auto-Submit: Joshua Bell <jsbell@chromium.org>
Commit-Queue: Marijn Kruisselbrink <mek@chromium.org>
Reviewed-by: Marijn Kruisselbrink <mek@chromium.org>
Cr-Commit-Position: refs/heads/master@{#736634}

content/browser/locks/lock_manager.h

@@ -9,7 +9,6 @@
 #include <string>
 
 #include "base/callback.h"
-#include "base/memory/ref_counted.h"
 #include "base/sequence_checker.h"
 #include "content/public/browser/browser_context.h"
 #include "mojo/public/cpp/bindings/receiver_set.h"
@@ -21,10 +20,10 @@ namespace content {
 // One instance of this exists per StoragePartition, and services multiple
 // child processes/origins. An instance must only be used on the sequence
 // it was created on.
-class LockManager : public base::RefCountedThreadSafe<LockManager>,
-                    public blink::mojom::LockManager {
+class LockManager : public blink::mojom::LockManager {
  public:
   LockManager();
+  ~LockManager() override;
 
   // Binds |receiver| to this LockManager. |receiver| belongs to a frame or
   // worker at |origin| hosted by |render_process_id|. If it belongs to a frame,
@@ -48,10 +47,6 @@ class LockManager : public base::RefCountedThreadSafe<LockManager>,
   // Called to request a snapshot of the current lock state for an origin.
   void QueryState(QueryStateCallback callback) override;
 
- protected:
-  friend class base::RefCountedThreadSafe<LockManager>;
-  ~LockManager() override;
-
  private:
   // Internal representation of a lock request or held lock.
   class Lock;

content/browser/storage_partition_impl.cc

@@ -1318,7 +1318,7 @@ void StoragePartitionImpl::Initialize() {
       relative_partition_path_, browser_context_->GetSpecialStoragePolicy());
 
   idle_manager_ = std::make_unique<IdleManager>();
-  lock_manager_ = new LockManager();
+  lock_manager_ = std::make_unique<LockManager>();
 
   base::FilePath path = is_in_memory_ ? base::FilePath() : partition_path_;
   indexed_db_context_ = new IndexedDBContextImpl(

content/browser/storage_partition_impl.h

@@ -436,7 +436,7 @@ class CONTENT_EXPORT StoragePartitionImpl
   scoped_refptr<storage::DatabaseTracker> database_tracker_;
   scoped_refptr<DOMStorageContextWrapper> dom_storage_context_;
   std::unique_ptr<IdleManager> idle_manager_;
-  scoped_refptr<LockManager> lock_manager_;
+  std::unique_ptr<LockManager> lock_manager_;
   mojo::Remote<storage::mojom::IndexedDBControl> indexed_db_control_;
   scoped_refptr<IndexedDBContextImpl> indexed_db_context_;
   scoped_refptr<CacheStorageContextImpl> cache_storage_context_;