Avoid UTF8 to UTF16 to UTF8 conversions with base::Value.

There are a couple places that starts with UTF8 data and converts them
to UTF16 before passing them to base::Value. base::Value turns around
and converts it back to UTF8.

Fix some nits along the way.

Change-Id: I10ad741de22aecc04b37fa633ab0033a26acc688
Reviewed-on: https://chromium-review.googlesource.com/1188033Reviewed-by: Jonathan Ross <jonross@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
Cr-Commit-Position: refs/heads/master@{#585848}

components/printing/renderer/print_render_frame_helper.cc

@@ -22,7 +22,6 @@
 #include "base/single_thread_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
-#include "base/strings/utf_string_conversions.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "components/grit/components_resources.h"
@@ -634,9 +633,8 @@ void PrintRenderFrameHelper::PrintHeaderAndFooter(
   blink::WebWidgetClient web_widget_client;
   blink::WebFrameWidget::Create(&web_widget_client, frame);
 
-  base::Value html(base::UTF8ToUTF16(
-      ui::ResourceBundle::GetSharedInstance().GetRawDataResource(
-          IDR_PRINT_HEADER_FOOTER_TEMPLATE_PAGE)));
+  base::Value html(ui::ResourceBundle::GetSharedInstance().GetRawDataResource(
+      IDR_PRINT_HEADER_FOOTER_TEMPLATE_PAGE));
   // Load page with script to avoid async operations.
   ExecuteScript(frame, kPageLoadScriptFormat, html);
 
@@ -1850,7 +1848,6 @@ bool PrintRenderFrameHelper::UpdatePrintSettings(
   }
 
   bool source_is_html = !PrintingNodeOrPdfFrame(frame, node);
-
   if (!source_is_html) {
     modified_job_settings.MergeDictionary(job_settings);
     modified_job_settings.SetBoolean(kSettingHeaderFooterEnabled, false);
@@ -2408,7 +2405,7 @@ void PrintRenderFrameHelper::SetPrintPagesParams(
                                              settings.params.document_cookie));
 }
 
-PrintRenderFrameHelper::ScriptingThrottler::ScriptingThrottler() : count_(0) {}
+PrintRenderFrameHelper::ScriptingThrottler::ScriptingThrottler() = default;
 
 bool PrintRenderFrameHelper::ScriptingThrottler::IsAllowed(
     blink::WebLocalFrame* frame) {
@@ -2442,7 +2439,7 @@ bool PrintRenderFrameHelper::ScriptingThrottler::IsAllowed(
   }
 
   blink::WebString message(
-      blink::WebString::FromUTF8("Ignoring too frequent calls to print()."));
+      blink::WebString::FromASCII("Ignoring too frequent calls to print()."));
   frame->AddMessageToConsole(blink::WebConsoleMessage(
       blink::WebConsoleMessage::kLevelWarning, message));
   return false;

services/preferences/pref_service_factory_unittest.cc

@@ -60,8 +60,8 @@ class ServiceTestClient : public service_manager::test::ServiceTestClient,
       const std::string& name,
       service_manager::mojom::PIDReceiverPtr pid_receiver) override {
     if (name == prefs::mojom::kServiceName) {
-      pref_service_context_.reset(new service_manager::ServiceContext(
-          service_factory_.Run(), std::move(request)));
+      pref_service_context_ = std::make_unique<service_manager::ServiceContext>(
+          service_factory_.Run(), std::move(request));
     } else if (name == "prefs_unittest_helper") {
       test_helper_service_context_ =
           std::make_unique<service_manager::ServiceContext>(
@@ -95,8 +95,8 @@ class PrefServiceFactoryTest : public service_manager::test::ServiceTest {
 
  protected:
   void SetUp() override {
-    above_user_prefs_pref_store_ = new ValueMapPrefStore();
-    below_user_prefs_pref_store_ = new ValueMapPrefStore();
+    above_user_prefs_pref_store_ = base::MakeRefCounted<ValueMapPrefStore>();
+    below_user_prefs_pref_store_ = base::MakeRefCounted<ValueMapPrefStore>();
     auto user_prefs = base::MakeRefCounted<InMemoryPrefStore>();
     PrefServiceFactory factory;
     service_factory_ = std::make_unique<InProcessPrefServiceFactory>();
@@ -442,8 +442,7 @@ TEST_F(PrefServiceFactoryTest, MultipleClients_SubPrefUpdates_Basic) {
         EXPECT_EQ(base::ASCIIToUTF16("hello"), out);
       },
       [](ScopedDictionaryPrefUpdate* update) {
-        (*update)->SetKey("key.for.string16",
-                          base::Value(base::ASCIIToUTF16("prefs!")));
+        (*update)->SetKey("key.for.string16", base::Value("prefs!"));
         base::string16 out;
         ASSERT_TRUE(
             (*update)->GetStringWithoutPathExpansion("key.for.string16", &out));