Remove calls to MessageLoop::Run/RunUntilIdle from ios/.

ios/chrome/browser/web_resource/web_resource_util_unittest.cc

Index: ios/chrome/browser/web_resource/web_resource_util_unittest.cc
diff --git a/ios/chrome/browser/web_resource/web_resource_util_unittest.cc b/ios/chrome/browser/web_resource/web_resource_util_unittest.cc
index 15293a8b1fb8032a161d1116a6743b9a9f4e9b75..b070a3bd966a7cc82f0df0bcb78a4eab2f66f0d0 100644
--- a/ios/chrome/browser/web_resource/web_resource_util_unittest.cc
+++ b/ios/chrome/browser/web_resource/web_resource_util_unittest.cc
@@ -10,6 +10,7 @@
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
 #include "base/strings/stringprintf.h"
 #include "base/values.h"
 #include "ios/web/public/web_thread.h"
@@ -51,7 +52,7 @@ class WebResourceUtilTest : public testing::Test {
     EXPECT_FALSE(error_called_);
 
     web::WebThread::GetBlockingPool()->FlushForTesting();
-    loop_.RunUntilIdle();
+    base::RunLoop().RunUntilIdle();
   }
 
   base::MessageLoop loop_;