diff --git a/vendor/github.com/golang/mock/gomock/controller.go b/vendor/github.com/golang/mock/gomock/controller.go
new file mode 100644
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+++ b/vendor/github.com/golang/mock/gomock/controller.go
@@ -0,0 +1,336 @@
+// Copyright 2010 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// Package gomock is a mock framework for Go.
+//
+// Standard usage:
+//   (1) Define an interface that you wish to mock.
+//         type MyInterface interface {
+//           SomeMethod(x int64, y string)
+//         }
+//   (2) Use mockgen to generate a mock from the interface.
+//   (3) Use the mock in a test:
+//         func TestMyThing(t *testing.T) {
+//           mockCtrl := gomock.NewController(t)
+//           defer mockCtrl.Finish()
+//
+//           mockObj := something.NewMockMyInterface(mockCtrl)
+//           mockObj.EXPECT().SomeMethod(4, "blah")
+//           // pass mockObj to a real object and play with it.
+//         }
+//
+// By default, expected calls are not enforced to run in any particular order.
+// Call order dependency can be enforced by use of InOrder and/or Call.After.
+// Call.After can create more varied call order dependencies, but InOrder is
+// often more convenient.
+//
+// The following examples create equivalent call order dependencies.
+//
+// Example of using Call.After to chain expected call order:
+//
+//     firstCall := mockObj.EXPECT().SomeMethod(1, "first")
+//     secondCall := mockObj.EXPECT().SomeMethod(2, "second").After(firstCall)
+//     mockObj.EXPECT().SomeMethod(3, "third").After(secondCall)
+//
+// Example of using InOrder to declare expected call order:
+//
+//     gomock.InOrder(
+//         mockObj.EXPECT().SomeMethod(1, "first"),
+//         mockObj.EXPECT().SomeMethod(2, "second"),
+//         mockObj.EXPECT().SomeMethod(3, "third"),
+//     )
+package gomock
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"runtime"
+	"sync"
+)
+
+// A TestReporter is something that can be used to report test failures.  It
+// is satisfied by the standard library's *testing.T.
+type TestReporter interface {
+	Errorf(format string, args ...interface{})
+	Fatalf(format string, args ...interface{})
+}
+
+// TestHelper is a TestReporter that has the Helper method.  It is satisfied
+// by the standard library's *testing.T.
+type TestHelper interface {
+	TestReporter
+	Helper()
+}
+
+// cleanuper is used to check if TestHelper also has the `Cleanup` method. A
+// common pattern is to pass in a `*testing.T` to
+// `NewController(t TestReporter)`. In Go 1.14+, `*testing.T` has a cleanup
+// method. This can be utilized to call `Finish()` so the caller of this library
+// does not have to.
+type cleanuper interface {
+	Cleanup(func())
+}
+
+// A Controller represents the top-level control of a mock ecosystem.  It
+// defines the scope and lifetime of mock objects, as well as their
+// expectations.  It is safe to call Controller's methods from multiple
+// goroutines. Each test should create a new Controller and invoke Finish via
+// defer.
+//
+//   func TestFoo(t *testing.T) {
+//     ctrl := gomock.NewController(t)
+//     defer ctrl.Finish()
+//     // ..
+//   }
+//
+//   func TestBar(t *testing.T) {
+//     t.Run("Sub-Test-1", st) {
+//       ctrl := gomock.NewController(st)
+//       defer ctrl.Finish()
+//       // ..
+//     })
+//     t.Run("Sub-Test-2", st) {
+//       ctrl := gomock.NewController(st)
+//       defer ctrl.Finish()
+//       // ..
+//     })
+//   })
+type Controller struct {
+	// T should only be called within a generated mock. It is not intended to
+	// be used in user code and may be changed in future versions. T is the
+	// TestReporter passed in when creating the Controller via NewController.
+	// If the TestReporter does not implement a TestHelper it will be wrapped
+	// with a nopTestHelper.
+	T             TestHelper
+	mu            sync.Mutex
+	expectedCalls *callSet
+	finished      bool
+}
+
+// NewController returns a new Controller. It is the preferred way to create a
+// Controller.
+//
+// New in go1.14+, if you are passing a *testing.T into this function you no
+// longer need to call ctrl.Finish() in your test methods.
+func NewController(t TestReporter) *Controller {
+	h, ok := t.(TestHelper)
+	if !ok {
+		h = &nopTestHelper{t}
+	}
+	ctrl := &Controller{
+		T:             h,
+		expectedCalls: newCallSet(),
+	}
+	if c, ok := isCleanuper(ctrl.T); ok {
+		c.Cleanup(func() {
+			ctrl.T.Helper()
+			ctrl.finish(true, nil)
+		})
+	}
+
+	return ctrl
+}
+
+type cancelReporter struct {
+	t      TestHelper
+	cancel func()
+}
+
+func (r *cancelReporter) Errorf(format string, args ...interface{}) {
+	r.t.Errorf(format, args...)
+}
+func (r *cancelReporter) Fatalf(format string, args ...interface{}) {
+	defer r.cancel()
+	r.t.Fatalf(format, args...)
+}
+
+func (r *cancelReporter) Helper() {
+	r.t.Helper()
+}
+
+// WithContext returns a new Controller and a Context, which is cancelled on any
+// fatal failure.
+func WithContext(ctx context.Context, t TestReporter) (*Controller, context.Context) {
+	h, ok := t.(TestHelper)
+	if !ok {
+		h = &nopTestHelper{t: t}
+	}
+
+	ctx, cancel := context.WithCancel(ctx)
+	return NewController(&cancelReporter{t: h, cancel: cancel}), ctx
+}
+
+type nopTestHelper struct {
+	t TestReporter
+}
+
+func (h *nopTestHelper) Errorf(format string, args ...interface{}) {
+	h.t.Errorf(format, args...)
+}
+func (h *nopTestHelper) Fatalf(format string, args ...interface{}) {
+	h.t.Fatalf(format, args...)
+}
+
+func (h nopTestHelper) Helper() {}
+
+// RecordCall is called by a mock. It should not be called by user code.
+func (ctrl *Controller) RecordCall(receiver interface{}, method string, args ...interface{}) *Call {
+	ctrl.T.Helper()
+
+	recv := reflect.ValueOf(receiver)
+	for i := 0; i < recv.Type().NumMethod(); i++ {
+		if recv.Type().Method(i).Name == method {
+			return ctrl.RecordCallWithMethodType(receiver, method, recv.Method(i).Type(), args...)
+		}
+	}
+	ctrl.T.Fatalf("gomock: failed finding method %s on %T", method, receiver)
+	panic("unreachable")
+}
+
+// RecordCallWithMethodType is called by a mock. It should not be called by user code.
+func (ctrl *Controller) RecordCallWithMethodType(receiver interface{}, method string, methodType reflect.Type, args ...interface{}) *Call {
+	ctrl.T.Helper()
+
+	call := newCall(ctrl.T, receiver, method, methodType, args...)
+
+	ctrl.mu.Lock()
+	defer ctrl.mu.Unlock()
+	ctrl.expectedCalls.Add(call)
+
+	return call
+}
+
+// Call is called by a mock. It should not be called by user code.
+func (ctrl *Controller) Call(receiver interface{}, method string, args ...interface{}) []interface{} {
+	ctrl.T.Helper()
+
+	// Nest this code so we can use defer to make sure the lock is released.
+	actions := func() []func([]interface{}) []interface{} {
+		ctrl.T.Helper()
+		ctrl.mu.Lock()
+		defer ctrl.mu.Unlock()
+
+		expected, err := ctrl.expectedCalls.FindMatch(receiver, method, args)
+		if err != nil {
+			// callerInfo's skip should be updated if the number of calls between the user's test
+			// and this line changes, i.e. this code is wrapped in another anonymous function.
+			// 0 is us, 1 is controller.Call(), 2 is the generated mock, and 3 is the user's test.
+			origin := callerInfo(3)
+			ctrl.T.Fatalf("Unexpected call to %T.%v(%v) at %s because: %s", receiver, method, args, origin, err)
+		}
+
+		// Two things happen here:
+		// * the matching call no longer needs to check prerequite calls,
+		// * and the prerequite calls are no longer expected, so remove them.
+		preReqCalls := expected.dropPrereqs()
+		for _, preReqCall := range preReqCalls {
+			ctrl.expectedCalls.Remove(preReqCall)
+		}
+
+		actions := expected.call()
+		if expected.exhausted() {
+			ctrl.expectedCalls.Remove(expected)
+		}
+		return actions
+	}()
+
+	var rets []interface{}
+	for _, action := range actions {
+		if r := action(args); r != nil {
+			rets = r
+		}
+	}
+
+	return rets
+}
+
+// Finish checks to see if all the methods that were expected to be called
+// were called. It should be invoked for each Controller. It is not idempotent
+// and therefore can only be invoked once.
+//
+// New in go1.14+, if you are passing a *testing.T into NewController function you no
+// longer need to call ctrl.Finish() in your test methods.
+func (ctrl *Controller) Finish() {
+	// If we're currently panicking, probably because this is a deferred call.
+	// This must be recovered in the deferred function.
+	err := recover()
+	ctrl.finish(false, err)
+}
+
+func (ctrl *Controller) finish(cleanup bool, panicErr interface{}) {
+	ctrl.T.Helper()
+
+	ctrl.mu.Lock()
+	defer ctrl.mu.Unlock()
+
+	if ctrl.finished {
+		if _, ok := isCleanuper(ctrl.T); !ok {
+			ctrl.T.Fatalf("Controller.Finish was called more than once. It has to be called exactly once.")
+		}
+		return
+	}
+	ctrl.finished = true
+
+	// Short-circuit, pass through the panic.
+	if panicErr != nil {
+		panic(panicErr)
+	}
+
+	// Check that all remaining expected calls are satisfied.
+	failures := ctrl.expectedCalls.Failures()
+	for _, call := range failures {
+		ctrl.T.Errorf("missing call(s) to %v", call)
+	}
+	if len(failures) != 0 {
+		if !cleanup {
+			ctrl.T.Fatalf("aborting test due to missing call(s)")
+			return
+		}
+		ctrl.T.Errorf("aborting test due to missing call(s)")
+	}
+}
+
+// callerInfo returns the file:line of the call site. skip is the number
+// of stack frames to skip when reporting. 0 is callerInfo's call site.
+func callerInfo(skip int) string {
+	if _, file, line, ok := runtime.Caller(skip + 1); ok {
+		return fmt.Sprintf("%s:%d", file, line)
+	}
+	return "unknown file"
+}
+
+// isCleanuper checks it if t's base TestReporter has a Cleanup method.
+func isCleanuper(t TestReporter) (cleanuper, bool) {
+	tr := unwrapTestReporter(t)
+	c, ok := tr.(cleanuper)
+	return c, ok
+}
+
+// unwrapTestReporter unwraps TestReporter to the base implementation.
+func unwrapTestReporter(t TestReporter) TestReporter {
+	tr := t
+	switch nt := t.(type) {
+	case *cancelReporter:
+		tr = nt.t
+		if h, check := tr.(*nopTestHelper); check {
+			tr = h.t
+		}
+	case *nopTestHelper:
+		tr = nt.t
+	default:
+		// not wrapped
+	}
+	return tr
+}