[ios] Use SpinRunLoopWithMinDelay in MetaTagsTestCase.

base/test/ios/wait_util.mm

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "base/test/ios/wait_util.h"
 
 #import <Foundation/Foundation.h>
 
 #include "base/logging.h"
 #include "base/mac/scoped_nsobject.h"
@@ skipping 39 matching lines @@
   WaitUntilCondition(condition, nullptr, TimeDelta());
 }
 
 void SpinRunLoopWithMaxDelay(TimeDelta max_delay) {
   scoped_nsobject<NSDate> beforeDate(
       [[NSDate alloc] initWithTimeIntervalSinceNow:max_delay.InSecondsF()]);
   [[NSRunLoop currentRunLoop] runMode:NSDefaultRunLoopMode
                            beforeDate:beforeDate];
 }
 
+void SpinRunLoopWithMinDelay(TimeDelta min_delay) {
+  ElapsedTimer timer;
+  while (timer.Elapsed() < min_delay) {
+    SpinRunLoopWithMaxDelay(base::TimeDelta::FromMilliseconds(10));
+  }
+}
+
 }  // namespace ios
 }  // namespace test
 }  // namespace base