[WIP] Speculatively launch Service Workers on mouse/touch events.

chrome/browser/renderer_host/chrome_render_message_filter.cc

Index: chrome/browser/renderer_host/chrome_render_message_filter.cc
diff --git a/chrome/browser/renderer_host/chrome_render_message_filter.cc b/chrome/browser/renderer_host/chrome_render_message_filter.cc
index 1a48364b54c7839d39063d124d3d35240d9f2a58..6e630d2695dd325d173b857a69b175cb81786ba1 100644
--- a/chrome/browser/renderer_host/chrome_render_message_filter.cc
+++ b/chrome/browser/renderer_host/chrome_render_message_filter.cc
@@ -10,6 +10,7 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/feature_list.h"
 #include "base/logging.h"
 #include "base/macros.h"
 #include "base/metrics/field_trial.h"
@@ -31,6 +32,8 @@
 #include "components/web_cache/browser/web_cache_manager.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_process_host.h"
+#include "content/public/browser/storage_partition.h"
+#include "content/public/common/content_features.h"
 
 #if defined(ENABLE_EXTENSIONS)
 #include "extensions/browser/guest_view/web_view/web_view_permission_helper.h"
@@ -46,17 +49,23 @@ const uint32_t kFilteredMessageClasses[] = {
     ChromeMsgStart, ContentSettingsMsgStart, NetworkHintsMsgStart,
 };
 
+void DidStartServiceWorkerForNavigationHint(bool success) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+}
+
 }  // namespace
 
-ChromeRenderMessageFilter::ChromeRenderMessageFilter(int render_process_id,
-                                                     Profile* profile)
+ChromeRenderMessageFilter::ChromeRenderMessageFilter(
+    int render_process_id,
+    Profile* profile,
+    content::ServiceWorkerContext* service_worker_context)
     : BrowserMessageFilter(kFilteredMessageClasses,
                            arraysize(kFilteredMessageClasses)),
       render_process_id_(render_process_id),
       profile_(profile),
       predictor_(profile_->GetNetworkPredictor()),
-      cookie_settings_(CookieSettingsFactory::GetForProfile(profile)) {
-}
+      cookie_settings_(CookieSettingsFactory::GetForProfile(profile)),
+      service_worker_context_(service_worker_context) {}
 
 ChromeRenderMessageFilter::~ChromeRenderMessageFilter() {
 }
@@ -66,6 +75,7 @@ bool ChromeRenderMessageFilter::OnMessageReceived(const IPC::Message& message) {
   IPC_BEGIN_MESSAGE_MAP(ChromeRenderMessageFilter, message)
     IPC_MESSAGE_HANDLER(NetworkHintsMsg_DNSPrefetch, OnDnsPrefetch)
     IPC_MESSAGE_HANDLER(NetworkHintsMsg_Preconnect, OnPreconnect)
+    IPC_MESSAGE_HANDLER(NetworkHintsMsg_NavigationHint, OnNavigationHint)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_UpdatedCacheStats,
                         OnUpdatedCacheStats)
     IPC_MESSAGE_HANDLER(ChromeViewHostMsg_AllowDatabase, OnAllowDatabase)
@@ -128,6 +138,17 @@ void ChromeRenderMessageFilter::OnPreconnect(const GURL& url,
   }
 }
 
+void ChromeRenderMessageFilter::OnNavigationHint(
+    const GURL& url,
+    blink::WebNavigationHintType type) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+  DCHECK(
+      base::FeatureList::IsEnabled(features::kSpeculativeLaunchServiceWorker));
+  service_worker_context_->StartServiceWorkerForNavigationHint(
+      url, type, render_process_id_,
+      base::Bind(&DidStartServiceWorkerForNavigationHint));
+}
+
 void ChromeRenderMessageFilter::OnUpdatedCacheStats(
     uint64_t min_dead_capacity,
     uint64_t max_dead_capacity,