WebUIDataSource::AddInteger (like AddBoolean/AddString)

Convenience function to add integers to a WebUIDataSource
without using AddLocalizedStrings with a base::DictionaryValue.

Limits width to 32 bits to prevent integers larger than can
be represented in ES6 (2^53 - 1). (As before, larger numbers
could still be set via AddLocalizedStrings.)

BUG=none
R=tommycli@chromium.org,creis@chromium.org
TEST=content_unittests:WebUIDataSourceTest

Review-Url: https://codereview.chromium.org/2391073005
Cr-Commit-Position: refs/heads/master@{#423816}

chrome/browser/ui/webui/settings/chromeos/date_time_handler.cc

@@ -56,10 +56,8 @@ DateTimeHandler* DateTimeHandler::Create(
   html_source->AddBoolean("systemTimeZoneDetectionManaged",
       system_time_zone_automatic_detection_managed);
   if (system_time_zone_automatic_detection_managed) {
-    base::DictionaryValue dict;
-    dict.SetInteger("systemTimeZoneDetectionPolicyValue",
+    html_source->AddInteger("systemTimeZoneDetectionPolicyValue",
         GetSystemTimezoneAutomaticDetectionPolicyValue());
-    html_source->AddLocalizedStrings(dict);
   }
 
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(

content/browser/webui/web_ui_data_source_impl.cc

@@ -5,6 +5,7 @@
 #include "content/browser/webui/web_ui_data_source_impl.h"
 
 #include <stddef.h>
+#include <stdint.h>
 
 #include <string>
 
@@ -141,6 +142,10 @@ void WebUIDataSourceImpl::AddBoolean(const std::string& name, bool value) {
   // replacements.
 }
 
+void WebUIDataSourceImpl::AddInteger(const std::string& name, int32_t value) {
+  localized_strings_.SetInteger(name, value);
+}
+
 void WebUIDataSourceImpl::SetJsonPath(const std::string& path) {
   json_path_ = path;
 }

content/browser/webui/web_ui_data_source_impl.h

@@ -5,6 +5,8 @@
 #ifndef CONTENT_BROWSER_WEBUI_WEB_UI_DATA_SOURCE_IMPL_H_
 #define CONTENT_BROWSER_WEBUI_WEB_UI_DATA_SOURCE_IMPL_H_
 
+#include <stdint.h>
+
 #include <map>
 #include <string>
 
@@ -34,6 +36,7 @@ class CONTENT_EXPORT WebUIDataSourceImpl
   void AddLocalizedStrings(
       const base::DictionaryValue& localized_strings) override;
   void AddBoolean(const std::string& name, bool value) override;
+  void AddInteger(const std::string& name, int32_t value) override;
   void SetJsonPath(const std::string& path) override;
   void AddResourcePath(const std::string& path, int resource_id) override;
   void SetDefaultResource(int resource_id) override;

content/browser/webui/web_ui_data_source_unittest.cc

@@ -103,17 +103,23 @@ TEST_F(WebUIDataSourceTest, EmptyStrings) {
   StartDataRequest("strings.js", base::Bind(&EmptyStringsCallback));
 }
 
-void SomeStringsCallback(scoped_refptr<base::RefCountedMemory> data) {
+void SomeValuesCallback(scoped_refptr<base::RefCountedMemory> data) {
   std::string result(data->front_as<char>(), data->size());
+  EXPECT_NE(result.find("\"flag\":true"), std::string::npos);
+  EXPECT_NE(result.find("\"counter\":10"), std::string::npos);
+  EXPECT_NE(result.find("\"debt\":-456"), std::string::npos);
   EXPECT_NE(result.find("\"planet\":\"pluto\""), std::string::npos);
   EXPECT_NE(result.find("\"button\":\"foo\""), std::string::npos);
 }
 
-TEST_F(WebUIDataSourceTest, SomeStrings) {
+TEST_F(WebUIDataSourceTest, SomeValues) {
   source()->SetJsonPath("strings.js");
+  source()->AddBoolean("flag", true);
+  source()->AddInteger("counter", 10);
+  source()->AddInteger("debt", -456);
   source()->AddString("planet", base::ASCIIToUTF16("pluto"));
   source()->AddLocalizedString("button", kDummyStringId);
-  StartDataRequest("strings.js", base::Bind(&SomeStringsCallback));
+  StartDataRequest("strings.js", base::Bind(&SomeValuesCallback));
 }
 
 void DefaultResourceFoobarCallback(scoped_refptr<base::RefCountedMemory> data) {

content/public/browser/web_ui_data_source.h

@@ -5,6 +5,8 @@
 #ifndef CONTENT_PUBLIC_BROWSER_WEB_UI_DATA_SOURCE_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_UI_DATA_SOURCE_H_
 
+#include <stdint.h>
+
 #include "base/callback.h"
 #include "base/strings/string16.h"
 #include "content/common/content_export.h"
@@ -47,6 +49,11 @@ class WebUIDataSource {
   // Adds a boolean keyed to its name to our dictionary.
   virtual void AddBoolean(const std::string& name, bool value) = 0;
 
+  // Adds a signed 32-bit integer keyed to its name to our dictionary. Larger
+  // integers may not be exactly representable in JavaScript. See
+  // MAX_SAFE_INTEGER in /v8/src/globals.h.
+  virtual void AddInteger(const std::string& name, int32_t value) = 0;
+
   // Sets the path which will return the JSON strings.
   virtual void SetJsonPath(const std::string& path) = 0;