Make faster ProcessFeedService (#3080)

* Add index accounts on uri.

* Remove a blank line.

db/migrate/20170516072309_add_index_accounts_on_uri.rb

@@ -0,0 +1,5 @@
+class AddIndexAccountsOnUri < ActiveRecord::Migration[5.0]
+  def change
+    add_index :accounts, :uri
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20170508230434) do
+ActiveRecord::Schema.define(version: 20170516072309) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -50,6 +50,7 @@ ActiveRecord::Schema.define(version: 20170508230434) do
     t.datetime "last_webfingered_at"
     t.index "(((setweight(to_tsvector('simple'::regconfig, (display_name)::text), 'A'::\"char\") || setweight(to_tsvector('simple'::regconfig, (username)::text), 'B'::\"char\")) || setweight(to_tsvector('simple'::regconfig, (COALESCE(domain, ''::character varying))::text), 'C'::\"char\")))", name: "search_index", using: :gin
     t.index "lower((username)::text), lower((domain)::text)", name: "index_accounts_on_username_and_domain_lower", using: :btree
+    t.index ["uri"], name: "index_accounts_on_uri", using: :btree
     t.index ["url"], name: "index_accounts_on_url", using: :btree
     t.index ["username", "domain"], name: "index_accounts_on_username_and_domain", unique: true, using: :btree
   end