Expose client hints as a keyed service

Instead of static class, expose client hints as a keyed service.
Next CL would add a new abstract class client_hints_controller
in //content, and make client hints in //chrome, a derived class
of the client_hints_controller. This would allow
content to directly call the methods to determine which client
hint headers should be added.

Change-Id: I8971e77a23dd49f2f25ba8036ca8ea76c24ca2a4
Bug: 875703
Reviewed-on: https://chromium-review.googlesource.com/c/1368208
Commit-Queue: Tarun Bansal <tbansal@chromium.org>
Reviewed-by: Tarun Bansal <tbansal@chromium.org>
Reviewed-by: Ryan Sturm <ryansturm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#615826}

chrome/browser/BUILD.gn

@@ -278,6 +278,8 @@ jumbo_split_static_library("browser") {
     "chrome_service.h",
     "client_hints/client_hints.cc",
     "client_hints/client_hints.h",
+    "client_hints/client_hints_factory.cc",
+    "client_hints/client_hints_factory.h",
     "client_hints/client_hints_observer.cc",
     "client_hints/client_hints_observer.h",
     "clipboard/clipboard_read_permission_context.cc",

chrome/browser/chrome_content_browser_client.cc

@@ -40,6 +40,7 @@
 #include "chrome/browser/chrome_content_browser_client_parts.h"
 #include "chrome/browser/chrome_quota_permission_context.h"
 #include "chrome/browser/client_hints/client_hints.h"
+#include "chrome/browser/client_hints/client_hints_factory.h"
 #include "chrome/browser/content_settings/cookie_settings_factory.h"
 #include "chrome/browser/content_settings/host_content_settings_map_factory.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
@@ -2272,9 +2273,9 @@ void ChromeContentBrowserClient::NavigationRequestStarted(
   WebContents* web_contents =
       WebContents::FromFrameTreeNodeId(frame_tree_node_id);
   content::BrowserContext* browser_context = web_contents->GetBrowserContext();
-  *extra_headers =
-      client_hints::GetAdditionalNavigationRequestClientHintsHeaders(
-          browser_context, url);
+
+  *extra_headers = ClientHintsFactory::GetForBrowserContext(browser_context)
+                       ->GetAdditionalNavigationRequestClientHintsHeaders(url);
   prerender::PrerenderContents* prerender_contents =
       prerender::PrerenderContents::FromWebContents(web_contents);
   if (prerender_contents &&
@@ -2318,8 +2319,8 @@ void ChromeContentBrowserClient::NavigationRequestRedirected(
   }
 
   std::unique_ptr<net::HttpRequestHeaders> client_hints_extra_headers =
-      client_hints::GetAdditionalNavigationRequestClientHintsHeaders(
-          browser_context, url);
+      ClientHintsFactory::GetForBrowserContext(browser_context)
+          ->GetAdditionalNavigationRequestClientHintsHeaders(url);
   if (client_hints_extra_headers) {
     if (!modified_request_headers->has_value())
       *modified_request_headers = net::HttpRequestHeaders();

chrome/browser/client_hints/client_hints.cc

@@ -210,10 +210,14 @@ double RoundKbpsToMbps(const std::string& host,
 
 }  // namespace internal
 
+ClientHints::ClientHints(content::BrowserContext* context)
+    : context_(context) {}
+
+ClientHints::~ClientHints() = default;
+
 std::unique_ptr<net::HttpRequestHeaders>
-GetAdditionalNavigationRequestClientHintsHeaders(
-    content::BrowserContext* context,
-    const GURL& url) {
+ClientHints::GetAdditionalNavigationRequestClientHintsHeaders(
+    const GURL& url) const {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
   DCHECK_EQ(blink::kWebEffectiveConnectionTypeMappingCount,
             net::EFFECTIVE_CONNECTION_TYPE_4G + 1u);
@@ -233,7 +237,7 @@ GetAdditionalNavigationRequestClientHintsHeaders(
   DCHECK(url.SchemeIs(url::kHttpsScheme) ||
          (url.SchemeIs(url::kHttpScheme) && net::IsLocalhost(url)));
 
-  Profile* profile = Profile::FromBrowserContext(context);
+  Profile* profile = Profile::FromBrowserContext(context_);
   if (!profile)
     return nullptr;
 
@@ -274,7 +278,7 @@ GetAdditionalNavigationRequestClientHintsHeaders(
   if (web_client_hints.IsEnabled(blink::mojom::WebClientHintsType::kDpr)) {
     double device_scale_factor = GetDeviceScaleFactor();
 
-    double zoom_factor = GetZoomFactor(context, url);
+    double zoom_factor = GetZoomFactor(context_, url);
     additional_headers->SetHeader(
         blink::kClientHintsHeaderMapping[static_cast<int>(
             blink::mojom::WebClientHintsType::kDpr)],
@@ -293,7 +297,7 @@ GetAdditionalNavigationRequestClientHintsHeaders(
                           ->GetPrimaryDisplay()
                           .GetSizeInPixel()
                           .width()) /
-                     GetZoomFactor(context, url) / device_scale_factor;
+                     GetZoomFactor(context_, url) / device_scale_factor;
 #endif  // !OS_ANDROID
     DCHECK_LT(0, viewport_width);
     if (viewport_width > 0) {

chrome/browser/client_hints/client_hints.h

@@ -9,6 +9,7 @@
 
 #include "base/memory/ref_counted.h"
 #include "base/optional.h"
+#include "components/keyed_service/core/keyed_service.h"
 
 class GURL;
 
@@ -37,12 +38,21 @@ double RoundKbpsToMbps(const std::string& host,
 
 }  // namespace internal
 
-// Allow the embedder to return additional headers related to client hints that
-// should be sent when fetching |url|. May return a nullptr.
-std::unique_ptr<net::HttpRequestHeaders>
-GetAdditionalNavigationRequestClientHintsHeaders(
-    content::BrowserContext* context,
-    const GURL& url);
+class ClientHints : public KeyedService {
+ public:
+  explicit ClientHints(content::BrowserContext* context);
+  ~ClientHints() override;
+
+  // Allow the embedder to return additional headers related to client hints
+  // that should be sent when fetching |url|. May return a nullptr.
+  std::unique_ptr<net::HttpRequestHeaders>
+  GetAdditionalNavigationRequestClientHintsHeaders(const GURL& url) const;
+
+ private:
+  content::BrowserContext* context_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClientHints);
+};
 
 }  // namespace client_hints
 

chrome/browser/client_hints/client_hints_factory.cc

+// Copyright 2018 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 "chrome/browser/client_hints/client_hints_factory.h"
+
+#include "chrome/browser/client_hints/client_hints.h"
+#include "chrome/browser/profiles/incognito_helpers.h"
+#include "components/keyed_service/content/browser_context_dependency_manager.h"
+#include "content/public/browser/browser_context.h"
+
+namespace {
+
+base::LazyInstance<ClientHintsFactory>::DestructorAtExit
+    g_previews_service_factory = LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+// static
+client_hints::ClientHints* ClientHintsFactory::GetForBrowserContext(
+    content::BrowserContext* context) {
+  return static_cast<client_hints::ClientHints*>(
+      GetInstance()->GetServiceForContext(context, true));
+}
+
+// static
+ClientHintsFactory* ClientHintsFactory::GetInstance() {
+  return g_previews_service_factory.Pointer();
+}
+
+ClientHintsFactory::ClientHintsFactory()
+    : BrowserContextKeyedServiceFactory(
+          "ClientHints",
+          BrowserContextDependencyManager::GetInstance()) {}
+
+ClientHintsFactory::~ClientHintsFactory() {}
+
+KeyedService* ClientHintsFactory::BuildServiceInstanceFor(
+    content::BrowserContext* context) const {
+  return new client_hints::ClientHints(context);
+}
+
+content::BrowserContext* ClientHintsFactory::GetBrowserContextToUse(
+    content::BrowserContext* context) const {
+  return chrome::GetBrowserContextOwnInstanceInIncognito(context);
+}

chrome/browser/client_hints/client_hints_factory.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_CLIENT_HINTS_CLIENT_HINTS_FACTORY_H_
+#define CHROME_BROWSER_CLIENT_HINTS_CLIENT_HINTS_FACTORY_H_
+
+#include "base/lazy_instance.h"
+#include "base/macros.h"
+#include "components/keyed_service/content/browser_context_keyed_service_factory.h"
+
+namespace content {
+class BrowserContext;
+}
+
+namespace client_hints {
+class ClientHints;
+}
+
+class ClientHintsFactory : public BrowserContextKeyedServiceFactory {
+ public:
+  static client_hints::ClientHints* GetForBrowserContext(
+      content::BrowserContext* context);
+
+  static ClientHintsFactory* GetInstance();
+
+ private:
+  friend struct base::LazyInstanceTraitsBase<ClientHintsFactory>;
+
+  ClientHintsFactory();
+  ~ClientHintsFactory() override;
+
+  // BrowserContextKeyedServiceFactory:
+  KeyedService* BuildServiceInstanceFor(
+      content::BrowserContext* context) const override;
+  content::BrowserContext* GetBrowserContextToUse(
+      content::BrowserContext* context) const override;
+
+  DISALLOW_COPY_AND_ASSIGN(ClientHintsFactory);
+};
+
+#endif  // CHROME_BROWSER_CLIENT_HINTS_CLIENT_HINTS_FACTORY_H_