Broadcast prerender URLs to all render processes.

Before this change, a render-initiated navigation could only swap to a prerender if the prerender was created via a <link rel="prerender"> element from a RenderView within the same render process.

Now that we are experimenting with local-browsing based prerenders, this means that a lot of prerenders may never be used. The prerenders are created in the browser process, and need to be advertised to all render processes.

There is a slight risk that an owned render process can spy on some navigations that a user does due to the broadcast.

BUG=239180

Review URL: https://chromiumcodereview.appspot.com/15027009

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@200223 0039d316-1c4b-4281-b951-d872f2087c98

10 files changed, 89 insertions, 73 deletions

diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index 0302986..e8868ac 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -141,11 +141,6 @@ void PrerenderContents::Observer::OnPrerenderStopLoading(
     PrerenderContents* contents) {
 }
 
-void PrerenderContents::Observer::OnPrerenderAddAlias(
-    PrerenderContents* contents,
-    const GURL& alias_url) {
-}
-
 void PrerenderContents::Observer::OnPrerenderCreatedMatchCompleteReplacement(
     PrerenderContents* contents, PrerenderContents* replacement) {
 }
@@ -370,6 +365,15 @@ PrerenderContents::~PrerenderContents() {
   prerender_manager_->RecordFinalStatusWithMatchCompleteStatus(
       origin(), experiment_id(), match_complete_status(), final_status());
 
+  // Broadcast the removal of aliases.
+  for (content::RenderProcessHost::iterator host_iterator =
+           content::RenderProcessHost::AllHostsIterator();
+       !host_iterator.IsAtEnd();
+       host_iterator.Advance()) {
+    content::RenderProcessHost* host = host_iterator.GetCurrentValue();
+    host->Send(new PrerenderMsg_OnPrerenderRemoveAliases(alias_urls_));
+  }
+
   // If we still have a WebContents, clean up anything we need to and then
   // destroy it.
   if (prerender_contents_.get())
@@ -485,11 +489,6 @@ void PrerenderContents::NotifyPrerenderStop() {
   observer_list_.Clear();
 }
 
-void PrerenderContents::NotifyPrerenderAddAlias(const GURL& alias_url) {
-  FOR_EACH_OBSERVER(Observer, observer_list_, OnPrerenderAddAlias(this,
-                                                                  alias_url));
-}
-
 void PrerenderContents::NotifyPrerenderCreatedMatchCompleteReplacement(
     PrerenderContents* replacement) {
   FOR_EACH_OBSERVER(Observer, observer_list_,
@@ -531,7 +530,15 @@ bool PrerenderContents::AddAliasURL(const GURL& url) {
   }
 
   alias_urls_.push_back(url);
-  NotifyPrerenderAddAlias(url);
+
+  for (content::RenderProcessHost::iterator host_iterator =
+           content::RenderProcessHost::AllHostsIterator();
+       !host_iterator.IsAtEnd();
+       host_iterator.Advance()) {
+    content::RenderProcessHost* host = host_iterator.GetCurrentValue();
+    host->Send(new PrerenderMsg_OnPrerenderAddAlias(url));
+  }
+
   return true;
 }
 
diff --git a/chrome/browser/prerender/prerender_contents.h b/chrome/browser/prerender/prerender_contents.h
index b7e8776..4b3422c 100644
--- a/chrome/browser/prerender/prerender_contents.h
+++ b/chrome/browser/prerender/prerender_contents.h
@@ -81,11 +81,6 @@ class PrerenderContents : public content::NotificationObserver,
     // Signals that the prerender has stopped running.
     virtual void OnPrerenderStop(PrerenderContents* contents) = 0;
 
-    // Signals the discovery, through redirects, of a new alias for this
-    // prerender.
-    virtual void OnPrerenderAddAlias(PrerenderContents* contents,
-                                     const GURL& alias_url);
-
     // Signals that this prerender has just become a MatchComplete replacement.
     virtual void OnPrerenderCreatedMatchCompleteReplacement(
         PrerenderContents* contents, PrerenderContents* replacement);
@@ -298,7 +293,6 @@ class PrerenderContents : public content::NotificationObserver,
   void NotifyPrerenderStart();
   void NotifyPrerenderStopLoading();
   void NotifyPrerenderStop();
-  void NotifyPrerenderAddAlias(const GURL& alias_url);
   void NotifyPrerenderCreatedMatchCompleteReplacement(
       PrerenderContents* replacement);
 
diff --git a/chrome/browser/prerender/prerender_handle.cc b/chrome/browser/prerender/prerender_handle.cc
index b4ebcd8..877d202 100644
--- a/chrome/browser/prerender/prerender_handle.cc
+++ b/chrome/browser/prerender/prerender_handle.cc
@@ -115,15 +115,6 @@ void PrerenderHandle::OnPrerenderStop(PrerenderContents* prerender_contents) {
     observer_->OnPrerenderStop(this);
 }
 
-void PrerenderHandle::OnPrerenderAddAlias(PrerenderContents* prerender_contents,
-                                          const GURL& alias_url) {
-  DCHECK(CalledOnValidThread());
-  DCHECK(prerender_data_);
-  DCHECK_EQ(prerender_data_->contents(), prerender_contents);
-  if (observer_)
-    observer_->OnPrerenderAddAlias(this, alias_url);
-}
-
 void PrerenderHandle::OnPrerenderCreatedMatchCompleteReplacement(
     PrerenderContents* contents, PrerenderContents* replacement) {
   DCHECK(CalledOnValidThread());
diff --git a/chrome/browser/prerender/prerender_handle.h b/chrome/browser/prerender/prerender_handle.h
index 67cae39..3e2e946 100644
--- a/chrome/browser/prerender/prerender_handle.h
+++ b/chrome/browser/prerender/prerender_handle.h
@@ -41,11 +41,6 @@ class PrerenderHandle : public base::NonThreadSafe,
     // Signals that the prerender has stopped running.
     virtual void OnPrerenderStop(PrerenderHandle* handle) = 0;
 
-    // Signals the discovery, through redirects, of a new alias for this
-    // prerender.
-    virtual void OnPrerenderAddAlias(PrerenderHandle* handle,
-                                     const GURL& alias_url) = 0;
-
    protected:
     Observer();
     virtual ~Observer();
@@ -91,8 +86,6 @@ class PrerenderHandle : public base::NonThreadSafe,
   virtual void OnPrerenderStopLoading(PrerenderContents* prerender_contents)
       OVERRIDE;
   virtual void OnPrerenderStop(PrerenderContents* prerender_contents) OVERRIDE;
-  virtual void OnPrerenderAddAlias(PrerenderContents* prerender_contents,
-                                   const GURL& alias_url) OVERRIDE;
   virtual void OnPrerenderCreatedMatchCompleteReplacement(
       PrerenderContents* contents, PrerenderContents* replacement) OVERRIDE;
 
diff --git a/chrome/browser/prerender/prerender_link_manager.cc b/chrome/browser/prerender/prerender_link_manager.cc
index 8b099b9..14cdc6e 100644
--- a/chrome/browser/prerender/prerender_link_manager.cc
+++ b/chrome/browser/prerender/prerender_link_manager.cc
@@ -338,16 +338,4 @@ void PrerenderLinkManager::OnPrerenderStop(
   StartPrerenders();
 }
 
-void PrerenderLinkManager::OnPrerenderAddAlias(
-    PrerenderHandle* prerender_handle,
-    const GURL& alias_url) {
-  LinkPrerender* prerender = FindByPrerenderHandle(prerender_handle);
-  if (!prerender)
-    return;
-
-  Send(prerender->launcher_child_id,
-       new PrerenderMsg_OnPrerenderAddAlias(prerender->prerender_id,
-                                            alias_url));
-}
-
 }  // namespace prerender
diff --git a/chrome/browser/prerender/prerender_link_manager.h b/chrome/browser/prerender/prerender_link_manager.h
index bb8ea07..97d0377 100644
--- a/chrome/browser/prerender/prerender_link_manager.h
+++ b/chrome/browser/prerender/prerender_link_manager.h
@@ -121,8 +121,6 @@ class PrerenderLinkManager : public ProfileKeyedService,
   virtual void OnPrerenderStopLoading(PrerenderHandle* prerender_handle)
       OVERRIDE;
   virtual void OnPrerenderStop(PrerenderHandle* prerender_handle) OVERRIDE;
-  virtual void OnPrerenderAddAlias(PrerenderHandle* prerender_handle,
-                                   const GURL& alias_url) OVERRIDE;
 
   bool has_shutdown_;
 
diff --git a/chrome/common/prerender_messages.h b/chrome/common/prerender_messages.h
index 83dae32..d35ec68 100644
--- a/chrome/common/prerender_messages.h
+++ b/chrome/common/prerender_messages.h
@@ -54,10 +54,13 @@ IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderStopLoading,
                      int /* prerender_id */)
 
 // Signals to a launcher that a new alias has been added to a prerender.
-IPC_MESSAGE_CONTROL2(PrerenderMsg_OnPrerenderAddAlias,
-                     int /* prerender_id */,
+IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderAddAlias,
                      GURL /* url */)
 
+// Signals to a launcher that a new alias has been added to a prerender.
+IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderRemoveAliases,
+                     std::vector<GURL> /* urls */)
+
 // Signals to a launcher that a prerender is no longer running.
 IPC_MESSAGE_CONTROL1(PrerenderMsg_OnPrerenderStop,
                      int /* prerender_id */)
diff --git a/chrome/renderer/prerender/prerender_dispatcher.cc b/chrome/renderer/prerender/prerender_dispatcher.cc
index 7739fb5..c5d5c851 100644
--- a/chrome/renderer/prerender/prerender_dispatcher.cc
+++ b/chrome/renderer/prerender/prerender_dispatcher.cc
@@ -43,7 +43,6 @@ void PrerenderDispatcher::OnPrerenderStart(int prerender_id) {
     return;
 
   prerender.didStartPrerender();
-  OnPrerenderAddAlias(prerender_id, prerender.url());
 }
 
 void PrerenderDispatcher::OnPrerenderStopLoading(int prerender_id) {
@@ -58,11 +57,18 @@ void PrerenderDispatcher::OnPrerenderStopLoading(int prerender_id) {
   prerender.didSendLoadForPrerender();
 }
 
-void PrerenderDispatcher::OnPrerenderAddAlias(int prerender_id,
-                                              const GURL& url) {
-  DCHECK_NE(0u, prerenders_.count(prerender_id));
-  running_prerender_urls_.insert(
-      std::multimap<GURL, int>::value_type(url, prerender_id));
+void PrerenderDispatcher::OnPrerenderAddAlias(const GURL& alias) {
+  running_prerender_urls_.insert(alias);
+}
+
+void PrerenderDispatcher::OnPrerenderRemoveAliases(
+    const std::vector<GURL>& aliases) {
+  for (size_t i = 0; i < aliases.size(); ++i) {
+    std::multiset<GURL>::iterator it = running_prerender_urls_.find(aliases[i]);
+    if (it != running_prerender_urls_.end()) {
+      running_prerender_urls_.erase(it);
+    }
+  }
 }
 
 void PrerenderDispatcher::OnPrerenderStop(int prerender_id) {
@@ -78,17 +84,6 @@ void PrerenderDispatcher::OnPrerenderStop(int prerender_id) {
   // This may not be that big of a deal in practice, since the newly created tab
   // is unlikely to go to the prerendered page.
   prerenders_.erase(prerender_id);
-
-  std::multimap<GURL, int>::iterator it = running_prerender_urls_.begin();
-  while (it != running_prerender_urls_.end()) {
-    std::multimap<GURL, int>::iterator next = it;
-    ++next;
-
-    if (it->second == prerender_id)
-      running_prerender_urls_.erase(it);
-
-    it = next;
-  }
 }
 
 bool PrerenderDispatcher::OnControlMessageReceived(
@@ -99,6 +94,8 @@ bool PrerenderDispatcher::OnControlMessageReceived(
     IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderStopLoading,
                         OnPrerenderStopLoading)
     IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderAddAlias, OnPrerenderAddAlias)
+    IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderRemoveAliases,
+                        OnPrerenderRemoveAliases)
     IPC_MESSAGE_HANDLER(PrerenderMsg_OnPrerenderStop, OnPrerenderStop)
     IPC_MESSAGE_UNHANDLED(handled = false)
   IPC_END_MESSAGE_MAP()
diff --git a/chrome/renderer/prerender/prerender_dispatcher.h b/chrome/renderer/prerender/prerender_dispatcher.h
index fa011c3..88544a1 100644
--- a/chrome/renderer/prerender/prerender_dispatcher.h
+++ b/chrome/renderer/prerender/prerender_dispatcher.h
@@ -6,6 +6,8 @@
 #define CHROME_RENDERER_PRERENDER_PRERENDER_DISPATCHER_H_
 
 #include <map>
+#include <set>
+#include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
@@ -35,7 +37,8 @@ class PrerenderDispatcher : public content::RenderProcessObserver,
   // Message handlers for messages from the browser process.
   void OnPrerenderStart(int prerender_id);
   void OnPrerenderStopLoading(int prerender_id);
-  void OnPrerenderAddAlias(int prerender_id, const GURL& url);
+  void OnPrerenderAddAlias(const GURL& alias);
+  void OnPrerenderRemoveAliases(const std::vector<GURL>& aliases);
   void OnPrerenderStop(int prerender_id);
 
   // From RenderProcessObserver:
@@ -51,7 +54,7 @@ class PrerenderDispatcher : public content::RenderProcessObserver,
 
   // From the browser process, which prerenders are running, indexed by URL.
   // Updated by the browser processes as aliases are discovered.
-  std::multimap<GURL, int> running_prerender_urls_;
+  std::multiset<GURL> running_prerender_urls_;
 };
 
 }  // namespace prerender
diff --git a/chrome/renderer/prerender/prerender_dispatcher_unittest.cc b/chrome/renderer/prerender/prerender_dispatcher_unittest.cc
index e46cc94..0f6ca14 100644
--- a/chrome/renderer/prerender/prerender_dispatcher_unittest.cc
+++ b/chrome/renderer/prerender/prerender_dispatcher_unittest.cc
@@ -45,12 +45,18 @@ class PrerenderDispatcherTest : public testing::Test {
     prerender_dispatcher_.prerenders_[g_next_prerender_id] = WebPrerender();
 
     prerender_dispatcher_.OnPrerenderStart(g_next_prerender_id);
-    prerender_dispatcher_.OnPrerenderAddAlias(g_next_prerender_id, url);
+    prerender_dispatcher_.OnPrerenderAddAlias(url);
     return g_next_prerender_id++;
   }
 
-  void AddAliasToPrerender(int prerender_id, const GURL& url) {
-    prerender_dispatcher_.OnPrerenderAddAlias(prerender_id, url);
+  void AddAliasToPrerender(const GURL& url) {
+    prerender_dispatcher_.OnPrerenderAddAlias(url);
+  }
+
+  void RemoveAliasFromPrerender(const GURL& url) {
+    std::vector<GURL> urls;
+    urls.push_back(url);
+    prerender_dispatcher_.OnPrerenderRemoveAliases(urls);
   }
 
   void StopPrerender(int prerender_id) {
@@ -84,11 +90,11 @@ TEST_F(PrerenderDispatcherTest, PrerenderDispatcherMultipleAdd) {
 
   EXPECT_FALSE(IsPrerenderURL(foo_url));
   EXPECT_FALSE(IsPrerenderURL(bar_url));
-  int foo_id = StartPrerender(foo_url);
+  StartPrerender(foo_url);
   EXPECT_TRUE(IsPrerenderURL(foo_url));
   EXPECT_FALSE(IsPrerenderURL(bar_url));
 
-  AddAliasToPrerender(foo_id, foo_url);
+  AddAliasToPrerender(foo_url);
   EXPECT_TRUE(IsPrerenderURL(foo_url));
   EXPECT_FALSE(IsPrerenderURL(bar_url));
   EXPECT_EQ(2, GetCountForURL(foo_url));
@@ -106,6 +112,42 @@ TEST_F(PrerenderDispatcherTest, PrerenderDispatcherSingleRemove) {
   int foo_id = StartPrerender(foo_url);
   EXPECT_TRUE(IsPrerenderURL(foo_url));
   StopPrerender(foo_id);
+  EXPECT_TRUE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(1, GetCountForURL(foo_url));
+  RemoveAliasFromPrerender(foo_url);
+  EXPECT_FALSE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(0, GetCountForURL(foo_url));
+}
+
+TEST_F(PrerenderDispatcherTest, PrerenderDispatcherTooManyRemoves) {
+  GURL foo_url = GURL("http://foo.com");
+  EXPECT_FALSE(IsPrerenderURL(foo_url));
+  int foo_id = StartPrerender(foo_url);
+  EXPECT_TRUE(IsPrerenderURL(foo_url));
+  StopPrerender(foo_id);
+  EXPECT_TRUE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(1, GetCountForURL(foo_url));
+  RemoveAliasFromPrerender(foo_url);
+  EXPECT_FALSE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(0, GetCountForURL(foo_url));
+  RemoveAliasFromPrerender(foo_url);
+  EXPECT_FALSE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(0, GetCountForURL(foo_url));
+}
+
+TEST_F(PrerenderDispatcherTest, PrerenderDispatcherMultipleRemoves) {
+  GURL foo_url = GURL("http://foo.com");
+  EXPECT_FALSE(IsPrerenderURL(foo_url));
+  int foo_id = StartPrerender(foo_url);
+  EXPECT_TRUE(IsPrerenderURL(foo_url));
+  AddAliasToPrerender(foo_url);
+  StopPrerender(foo_id);
+  EXPECT_TRUE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(2, GetCountForURL(foo_url));
+  RemoveAliasFromPrerender(foo_url);
+  EXPECT_TRUE(IsPrerenderURL(foo_url));
+  EXPECT_EQ(1, GetCountForURL(foo_url));
+  RemoveAliasFromPrerender(foo_url);
   EXPECT_FALSE(IsPrerenderURL(foo_url));
   EXPECT_EQ(0, GetCountForURL(foo_url));
 }