Revert of Hook up the Push API with GCM's new ability to own encryption keys.

components/gcm_driver/crypto/gcm_key_store.cc

Index: components/gcm_driver/crypto/gcm_key_store.cc
diff --git a/components/gcm_driver/crypto/gcm_key_store.cc b/components/gcm_driver/crypto/gcm_key_store.cc
index 0086291f35537ed209973c79dee92ac0452b479e..d445efe383aa41a9af84f8f3c654631230919293 100644
--- a/components/gcm_driver/crypto/gcm_key_store.cc
+++ b/components/gcm_driver/crypto/gcm_key_store.cc
@@ -22,11 +22,11 @@
 
 GCMKeyStore::GCMKeyStore(
     const base::FilePath& key_store_path,
-    const scoped_refptr<base::SequencedTaskRunner>& blocking_task_runner)
+    scoped_refptr<base::SequencedTaskRunner> background_task_runner)
     : key_store_path_(key_store_path),
-      blocking_task_runner_(blocking_task_runner),
+      database_(new leveldb_proto::ProtoDatabaseImpl<EncryptionData>(
+                    background_task_runner)),
       state_(State::UNINITIALIZED) {
-  DCHECK(blocking_task_runner);
 }
 
 GCMKeyStore::~GCMKeyStore() {}
@@ -168,9 +168,6 @@
 
   state_ = State::INITIALIZING;
 
-  database_.reset(new leveldb_proto::ProtoDatabaseImpl<EncryptionData>(
-      blocking_task_runner_));
-
   database_->Init(key_store_path_,
                   base::Bind(&GCMKeyStore::DidInitialize, this));
 }