Instant: Use only one hidden WebContents per profile.

chrome/browser/instant/instant_loader.cc

-// Copyright 2012 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/instant/instant_loader.h"
-
-#include "chrome/browser/content_settings/tab_specific_content_settings.h"
-#include "chrome/browser/extensions/api/web_navigation/web_navigation_api.h"
-#include "chrome/browser/favicon/favicon_tab_helper.h"
-#include "chrome/browser/history/history_tab_helper.h"
-#include "chrome/browser/safe_browsing/safe_browsing_tab_observer.h"
-#include "chrome/browser/tab_contents/tab_util.h"
-#include "chrome/browser/ui/blocked_content/blocked_content_tab_helper.h"
-#include "chrome/browser/ui/bookmarks/bookmark_tab_helper.h"
-#include "chrome/browser/ui/search/search_tab_helper.h"
-#include "chrome/browser/ui/tab_contents/core_tab_helper.h"
-#include "content/public/browser/navigation_entry.h"
-#include "content/public/browser/notification_source.h"
-#include "content/public/browser/notification_types.h"
-#include "content/public/browser/render_widget_host_view.h"
-#include "content/public/browser/site_instance.h"
-#include "content/public/browser/web_contents_view.h"
-
-namespace {
-
-const int kStalePageTimeoutMS = 3 * 3600 * 1000;  // 3 hours
-
-// This HTTP header and value are set on loads that originate from Instant.
-const char kInstantHeader[] = "X-Purpose: Instant";
-
-}  // namespace
-
-InstantLoader::Delegate::~Delegate() {
-}
-
-InstantLoader::InstantLoader(Delegate* delegate)
-  : delegate_(delegate),
-    contents_(NULL),
-    stale_page_timer_(false, false) {
-}
-
-InstantLoader::~InstantLoader() {
-}
-
-void InstantLoader::Init(const GURL& instant_url,
-                         Profile* profile,
-                         const content::WebContents* active_tab,
-                         const base::Closure& on_stale_callback) {
-  content::WebContents::CreateParams create_params(profile);
-  create_params.site_instance = content::SiteInstance::CreateForURL(
-      profile, instant_url);
-  SetContents(scoped_ptr<content::WebContents>(
-      content::WebContents::Create(create_params)));
-  instant_url_ = instant_url;
-  on_stale_callback_ = on_stale_callback;
-}
-
-void InstantLoader::Load() {
-  DVLOG(1) << "LoadURL: " << instant_url_;
-  contents_->GetController().LoadURL(
-      instant_url_, content::Referrer(),
-      content::PAGE_TRANSITION_GENERATED, kInstantHeader);
-  contents_->WasHidden();
-  stale_page_timer_.Start(
-      FROM_HERE,
-      base::TimeDelta::FromMilliseconds(kStalePageTimeoutMS),
-      on_stale_callback_);
-}
-
-void InstantLoader::SetContents(scoped_ptr<content::WebContents> new_contents) {
-  contents_.reset(new_contents.release());
-  contents_->SetDelegate(this);
-
-  // Set up various tab helpers. The rest will get attached when (if) the
-  // contents is added to the tab strip.
-
-  // Tab helpers to control popups.
-  BlockedContentTabHelper::CreateForWebContents(contents());
-  BlockedContentTabHelper::FromWebContents(contents())->
-      SetAllContentsBlocked(true);
-  TabSpecificContentSettings::CreateForWebContents(contents());
-  TabSpecificContentSettings::FromWebContents(contents())->
-      SetPopupsBlocked(true);
-
-  // Bookmarks (Users can bookmark the Instant NTP. This ensures the bookmarked
-  // state is correctly set when the contents are swapped into a tab.)
-  BookmarkTabHelper::CreateForWebContents(contents());
-
-  // A tab helper to catch prerender content swapping shenanigans.
-  CoreTabHelper::CreateForWebContents(contents());
-  CoreTabHelper::FromWebContents(contents())->set_delegate(this);
-
-  // Tab helpers used when committing an overlay.
-  chrome::search::SearchTabHelper::CreateForWebContents(contents());
-  HistoryTabHelper::CreateForWebContents(contents());
-
-  // Observers.
-  extensions::WebNavigationTabObserver::CreateForWebContents(contents());
-
-  // Favicons, required by the Task Manager.
-  FaviconTabHelper::CreateForWebContents(contents());
-
-  // And some flat-out paranoia.
-  safe_browsing::SafeBrowsingTabObserver::CreateForWebContents(contents());
-
-#if defined(OS_MACOSX)
-  // If |contents_| doesn't yet have a RWHV, SetTakesFocusOnlyOnMouseDown() will
-  // be called later, when NOTIFICATION_RENDER_VIEW_HOST_CHANGED is received.
-  if (content::RenderWidgetHostView* rwhv =
-          contents_->GetRenderWidgetHostView())
-    rwhv->SetTakesFocusOnlyOnMouseDown(true);
-  registrar_.Add(this, content::NOTIFICATION_RENDER_VIEW_HOST_CHANGED,
-                 content::Source<content::NavigationController>(
-                     &contents_->GetController()));
-#endif
-}
-
-scoped_ptr<content::WebContents> InstantLoader::ReleaseContents() {
-  contents_->SetDelegate(NULL);
-
-  // Undo tab helper work done in SetContents().
-
-  BlockedContentTabHelper::FromWebContents(contents())->
-      SetAllContentsBlocked(false);
-  TabSpecificContentSettings::FromWebContents(contents())->
-      SetPopupsBlocked(false);
-
-  CoreTabHelper::FromWebContents(contents())->set_delegate(NULL);
-
-#if defined(OS_MACOSX)
-  if (content::RenderWidgetHostView* rwhv =
-          contents_->GetRenderWidgetHostView())
-    rwhv->SetTakesFocusOnlyOnMouseDown(false);
-  registrar_.Remove(this, content::NOTIFICATION_RENDER_VIEW_HOST_CHANGED,
-                    content::Source<content::NavigationController>(
-                        &contents_->GetController()));
-#endif
-
-  return contents_.Pass();
-}
-
-void InstantLoader::Observe(int type,
-                            const content::NotificationSource& /* source */,
-                            const content::NotificationDetails& /* details */) {
-#if defined(OS_MACOSX)
-  if (type == content::NOTIFICATION_RENDER_VIEW_HOST_CHANGED) {
-    if (content::RenderWidgetHostView* rwhv =
-            contents_->GetRenderWidgetHostView())
-      rwhv->SetTakesFocusOnlyOnMouseDown(true);
-    return;
-  }
-  NOTREACHED();
-#endif
-}
-
-void InstantLoader::SwapTabContents(content::WebContents* old_contents,
-                                    content::WebContents* new_contents) {
-  DCHECK_EQ(old_contents, contents());
-  // We release here without deleting since the caller has the responsibility
-  // for deleting the old WebContents.
-  ignore_result(ReleaseContents().release());
-  SetContents(scoped_ptr<content::WebContents>(new_contents));
-  delegate_->OnSwappedContents();
-}
-
-bool InstantLoader::ShouldSuppressDialogs() {
-  // Messages shown during Instant cancel Instant, so we suppress them.
-  return true;
-}
-
-bool InstantLoader::ShouldFocusPageAfterCrash() {
-  return false;
-}
-
-void InstantLoader::LostCapture() {
-  delegate_->OnMouseUp();
-}
-
-void InstantLoader::WebContentsFocused(content::WebContents* /* contents */) {
-  delegate_->OnFocus();
-}
-
-bool InstantLoader::CanDownload(content::RenderViewHost* /* render_view_host */,
-                                int /* request_id */,
-                                const std::string& /* request_method */) {
-  // Downloads are disabled.
-  return false;
-}
-
-void InstantLoader::HandleMouseDown() {
-  delegate_->OnMouseDown();
-}
-
-void InstantLoader::HandleMouseUp() {
-  delegate_->OnMouseUp();
-}
-
-void InstantLoader::HandlePointerActivate() {
-  delegate_->OnMouseDown();
-}
-
-void InstantLoader::HandleGestureEnd() {
-  delegate_->OnMouseUp();
-}
-
-void InstantLoader::DragEnded() {
-  // If the user drags, we won't get a mouse up (at least on Linux). Commit
-  // the Instant result when the drag ends, so that during the drag the page
-  // won't move around.
-  delegate_->OnMouseUp();
-}
-
-bool InstantLoader::OnGoToEntryOffset(int /* offset */) {
-  return false;
-}
-
-content::WebContents* InstantLoader::OpenURLFromTab(
-    content::WebContents* source,
-    const content::OpenURLParams& params) {
-  return delegate_->OpenURLFromTab(source, params);
-}