Remove a chrome dependency by removing Prerender from ResourceDispatcherHost.

chrome/browser/prerender/prerender_tracker.cc

Index: chrome/browser/prerender/prerender_tracker.cc
diff --git a/chrome/browser/prerender/prerender_tracker.cc b/chrome/browser/prerender/prerender_tracker.cc
index c82acd339abb56742fb77c8bdfc4d9682b7dc20b..403b1bbb120033b00142635b211b4610c7899ff5 100644
--- a/chrome/browser/prerender/prerender_tracker.cc
+++ b/chrome/browser/prerender/prerender_tracker.cc
@@ -3,9 +3,13 @@
 // found in the LICENSE file.
 
 #include "base/logging.h"
+#include "chrome/browser/browser_process.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/prerender/prerender_tracker.h"
 #include "content/browser/browser_thread.h"
+#include "content/browser/resource_context.h"
+#include "content/common/resource_messages.h"
+#include "net/base/load_flags.h"
 
 namespace prerender {
 
@@ -28,19 +32,19 @@ void DestroyPreloadForRenderView(
 
 }  // namespace
 
-struct RenderViewInfo {
-  explicit RenderViewInfo(PrerenderManager* prerender_manager)
+PrerenderTracker::RenderViewInfo::RenderViewInfo(
+    PrerenderManager* prerender_manager)
       : final_status(FINAL_STATUS_MAX),
         prerender_manager(prerender_manager->AsWeakPtr()) {
-  }
+}
 
-  FinalStatus final_status;
-  base::WeakPtr<PrerenderManager> prerender_manager;
-};
+PrerenderTracker::RenderViewInfo::~RenderViewInfo() {
+}
 
-// static
-PrerenderTracker* PrerenderTracker::GetInstance() {
-  return Singleton<PrerenderTracker>::get();
+PrerenderTracker::PrerenderTracker() {
+}
+
+PrerenderTracker::~PrerenderTracker() {
 }
 
 bool PrerenderTracker::TryUse(int child_id, int route_id) {
@@ -74,15 +78,6 @@ bool PrerenderTracker::TryCancelOnIOThread(
   return TryCancel(child_id, route_id, final_status);
 }
 
-bool PrerenderTracker::IsPrerenderingOnIOThread(int child_id,
-                                                int route_id) const {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-
-  ChildRouteIdPair child_route_id_pair(child_id, route_id);
-  return possibly_prerendering_io_thread_set_.end() !=
-         possibly_prerendering_io_thread_set_.find(child_route_id_pair);
-}
-
 bool PrerenderTracker::GetFinalStatus(int child_id, int route_id,
                                       FinalStatus* final_status) const {
   ChildRouteIdPair child_route_id_pair(child_id, route_id);
@@ -134,12 +129,6 @@ void PrerenderTracker::OnPrerenderingFinished(int child_id, int route_id) {
   DCHECK_EQ(1u, num_erased);
 }
 
-PrerenderTracker::PrerenderTracker() {
-}
-
-PrerenderTracker::~PrerenderTracker() {
-}
-
 FinalStatus PrerenderTracker::SetFinalStatus(int child_id, int route_id,
                                              FinalStatus final_status) {
   DCHECK(final_status >= FINAL_STATUS_USED && final_status < FINAL_STATUS_MAX);
@@ -169,6 +158,62 @@ FinalStatus PrerenderTracker::SetFinalStatus(int child_id, int route_id,
   return final_status_it->second.final_status;
 }
 
+bool PrerenderTracker::ShouldBeginRequest(
+    int child_id, int route_id,
+    const ResourceHostMsg_Request& request_data,
+    const content::ResourceContext& resource_context,
+    const GURL& referrer) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  bool is_prerendering = IsPrerenderingOnIOThread(child_id, route_id);
+
+  // Handle a PREFETCH resource type.
+  if (request_data.resource_type == ResourceType::PREFETCH) {
+    // All PREFETCH requests should be GETs, but be defensive about it.
+    if (request_data.method != "GET")
+      return false;
+
+    // If prefetch is disabled, kill the request.
+    if (!ResourceDispatcherHost::is_prefetch_enabled())
+      return false;
+
+    // If prerendering is enabled, trigger a prerender for the URL and abort the
+    // request to prevent double-gets.
+    if (PrerenderManager::IsPrerenderingPossible()) {
+      BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+          NewRunnableFunction(HandlePrefetchTag,
+              resource_context.prerender_manager(),
+              child_id,
+              route_id,
+              request_data.url,
+              referrer,
+              is_prerendering));
+      return false;
+    }
+  }
+
+  // Abort any prerenders that spawn requests that use invalid HTTP methods.
+  if (is_prerendering &&
+      !PrerenderManager::IsValidHttpMethod(request_data.method)) {
+    BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+                            NewRunnableFunction(
+                                DestroyPreloadForRenderView,
+                                resource_context.prerender_manager(),
+                                child_id,
+                                route_id,
+                                FINAL_STATUS_INVALID_HTTP_METHOD));
+    return false;
+  }
+
+  return true;
+}
+
+void PrerenderTracker::MutateLoadFlags(int child_id, int route_id,
+                                       int* load_flags) {
+  DCHECK(load_flags);
+  if (IsPrerenderingOnIOThread(child_id, route_id))
+    *load_flags |= net::LOAD_PRERENDER;
+}
+
 void PrerenderTracker::AddPrerenderOnIOThread(
     const ChildRouteIdPair& child_route_id_pair) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
@@ -187,16 +232,27 @@ void PrerenderTracker::RemovePrerenderOnIOThread(
   possibly_prerendering_io_thread_set_.erase(child_route_id_pair);
 }
 
+bool PrerenderTracker::IsPrerenderingOnIOThread(int child_id,
+                                                int route_id) const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  ChildRouteIdPair child_route_id_pair(child_id, route_id);
+  return possibly_prerendering_io_thread_set_.end() !=
+         possibly_prerendering_io_thread_set_.find(child_route_id_pair);
+}
+
 // static
 void PrerenderTracker::AddPrerenderOnIOThreadTask(
     const ChildRouteIdPair& child_route_id_pair) {
-  GetInstance()->AddPrerenderOnIOThread(child_route_id_pair);
+  g_browser_process->prerender_tracker()->AddPrerenderOnIOThread(
+      child_route_id_pair);
 }
 
 // static
 void PrerenderTracker::RemovePrerenderOnIOThreadTask(
     const ChildRouteIdPair& child_route_id_pair) {
-  GetInstance()->RemovePrerenderOnIOThread(child_route_id_pair);
+  g_browser_process->prerender_tracker()->RemovePrerenderOnIOThread(
+      child_route_id_pair);
 }
 
 }  // namespace prerender