Implement chrome://histograms with network service.

content/browser/webui/web_ui_url_loader_factory.cc

 // Copyright 2017 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 "content/browser/webui/web_ui_url_loader_factory.h"
 
 #include <map>
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/memory/ref_counted_memory.h"
 #include "base/strings/string_piece.h"
 #include "content/browser/blob_storage/blob_internals_url_loader.h"
 #include "content/browser/blob_storage/chrome_blob_storage_context.h"
 #include "content/browser/frame_host/frame_tree_node.h"
 #include "content/browser/frame_host/render_frame_host_impl.h"
+#include "content/browser/histogram_internals_url_loader.h"
 #include "content/browser/resource_context_impl.h"
 #include "content/browser/webui/url_data_manager_backend.h"
 #include "content/browser/webui/url_data_source_impl.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/common/url_constants.h"
 #include "mojo/public/cpp/bindings/binding_set.h"
 #include "third_party/zlib/google/compression_utils.h"
@@ skipping 212 matching lines @@
                             mojom::URLLoaderClientPtr client) override {
     DCHECK_CURRENTLY_ON(BrowserThread::UI);
     if (request.url.host_piece() == kChromeUIBlobInternalsHost) {
       BrowserThread::PostTask(
           BrowserThread::IO, FROM_HERE,
           base::BindOnce(
               &StartBlobInternalsURLLoader, request, client.PassInterface(),
               base::Unretained(
                   ChromeBlobStorageContext::GetFor(browser_context_))));
       return;
+    } else if (request.url.host_piece() == kChromeUIHistogramHost) {
+      StartHistogramInternalsURLLoader(request, std::move(client));
+      return;
     }
 
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         base::BindOnce(&StartURLLoader, request, frame_tree_node_id_,
                        client.PassInterface(),
                        browser_context_->GetResourceContext()));
   }
 
   void SyncLoad(int32_t routing_id,
@@ skipping 19 matching lines @@
 }  // namespace
 
 mojom::URLLoaderFactoryPtr GetWebUIURLLoader(FrameTreeNode* node) {
   int ftn_id = node->frame_tree_node_id();
   if (g_factories.Get()[ftn_id].get() == nullptr)
     g_factories.Get()[ftn_id] = base::MakeUnique<WebUIURLLoaderFactory>(node);
   return g_factories.Get()[ftn_id]->CreateBinding();
 }
 
 }  // namespace content