Upstream most of the iOS WebUI support in ios/web/

ios/web/webui/shared_resources_data_source_ios.cc

+// 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.
+
+#include "ios/web/webui/shared_resources_data_source_ios.h"
+
+#include "base/logging.h"
+#include "base/memory/ref_counted_memory.h"
+#include "base/strings/string_util.h"
+#include "base/threading/thread_restrictions.h"
+#include "grit/webui_resources_map.h"
+#include "ios/web/public/web_client.h"
+#include "net/base/mime_util.h"
+#include "ui/base/webui/web_ui_util.h"
+#include "ui/resources/grit/webui_resources.h"
+
+namespace web {
+
+namespace {
+
+// Value duplicated from content/public/common/url_constants.h
+// TODO(stuartmorgan): Revisit how to share this in a more maintainable way.
+const char kWebUIResourcesHost[] = "resources";
+
+int PathToIDR(const std::string& path) {
+  int idr = -1;
+  for (size_t i = 0; i < kWebuiResourcesSize; ++i) {
+    if (path == kWebuiResources[i].name) {
+      idr = kWebuiResources[i].value;
+      break;
+    }
+  }
+
+  return idr;
+}
+
+}  // namespace
+
+SharedResourcesDataSourceIOS::SharedResourcesDataSourceIOS() {
+}
+
+SharedResourcesDataSourceIOS::~SharedResourcesDataSourceIOS() {
+}
+
+std::string SharedResourcesDataSourceIOS::GetSource() const {
+  return kWebUIResourcesHost;
+}
+
+void SharedResourcesDataSourceIOS::StartDataRequest(
+    const std::string& path,
+    const URLDataSourceIOS::GotDataCallback& callback) {
+  int idr = PathToIDR(path);
+  DCHECK_NE(-1, idr) << " path: " << path;
+  scoped_refptr<base::RefCountedMemory> bytes;
+
+  WebClient* web_client = GetWebClient();
+
+  if (idr == IDR_WEBUI_CSS_TEXT_DEFAULTS) {
+    std::vector<std::string> placeholders;
+    placeholders.push_back(webui::GetTextDirection());  // $1
+    placeholders.push_back(webui::GetFontFamily());  // $2
+    placeholders.push_back(webui::GetFontSize());  // $3
+
+    const std::string& chrome_shared =
+        web_client->GetDataResource(idr, ui::SCALE_FACTOR_NONE).as_string();
+    std::string replaced =
+        ReplaceStringPlaceholders(chrome_shared, placeholders, nullptr);
+    bytes = base::RefCountedString::TakeString(&replaced);
+  } else {
+    bytes = web_client->GetDataResourceBytes(idr);
+  }
+
+  callback.Run(bytes.get());
+}
+
+std::string SharedResourcesDataSourceIOS::GetMimeType(
+    const std::string& path) const {
+  std::string mime_type;
+  net::GetMimeTypeFromFile(base::FilePath().AppendASCII(path), &mime_type);
+  return mime_type;
+}
+
+}  // namespace web