[ios] Moved WebUI provider code to ios/web.

ios/chrome/browser/ui/webui/history/metrics_handler.cc

 // Copyright 2016 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.
 
 #include "ios/chrome/browser/ui/webui/history/metrics_handler.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
 #include "base/metrics/user_metrics.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
-#include "ios/public/provider/web/web_ui_ios.h"
+#include "ios/web/public/webui/web_ui_ios.h"
 
 using base::ListValue;
 using base::UserMetricsAction;
 
 MetricsHandler::MetricsHandler() {}
 MetricsHandler::~MetricsHandler() {}
 
 void MetricsHandler::RegisterMessages() {
   web_ui()->RegisterMessageCallback(
       "metricsHandler:recordAction",
@@ skipping 32 matching lines @@
     bucket_count /= 10;
   }
 
   // As |histogram_name| may change between calls, the UMA_HISTOGRAM_ENUMERATION
   // macro cannot be used here.
   base::HistogramBase* counter = base::LinearHistogram::FactoryGet(
       histogram_name, 1, int_boundary_value, bucket_count + 1,
       base::HistogramBase::kUmaTargetedHistogramFlag);
   counter->Add(int_value);
 }