[New Tab Page] Change the mechanism to intercept online NTP errors

chrome/browser/ui/search/search_tab_helper.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/ui/search/search_tab_helper.h"
 
 #include <set>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/histogram.h"
@@ skipping 37 matching lines @@
 #include "content/public/common/referrer.h"
 #include "net/base/net_errors.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/page_transition_types.h"
 #include "url/gurl.h"
 
 DEFINE_WEB_CONTENTS_USER_DATA_KEY(SearchTabHelper);
 
 namespace {
 
-// For reporting Cacheable NTP navigations.
-enum CacheableNTPLoad {
-  CACHEABLE_NTP_LOAD_FAILED = 0,
-  CACHEABLE_NTP_LOAD_SUCCEEDED = 1,
-  CACHEABLE_NTP_LOAD_MAX = 2
-};
-
-void RecordCacheableNTPLoadHistogram(bool succeeded) {
-  UMA_HISTOGRAM_ENUMERATION("InstantExtended.CacheableNTPLoad",
-                            succeeded ? CACHEABLE_NTP_LOAD_SUCCEEDED :
-                                CACHEABLE_NTP_LOAD_FAILED,
-                            CACHEABLE_NTP_LOAD_MAX);
-}
-
 bool IsCacheableNTP(const content::WebContents* contents) {
   const content::NavigationEntry* entry =
       contents->GetController().GetLastCommittedEntry();
   return chrome::NavEntryIsInstantNTP(contents, entry) &&
       entry->GetURL() != GURL(chrome::kChromeSearchLocalNtpUrl);
 }
 
 bool IsNTP(const content::WebContents* contents) {
   // We can't use WebContents::GetURL() because that uses the active entry,
   // whereas we want the visible entry.
@@ skipping 221 matching lines @@
         web_contents_->GetController().GetPendingEntry();
     if (entry)
       entry->SetTitle(l10n_util::GetStringUTF16(IDS_NEW_TAB_TITLE));
   }
 }
 
 void SearchTabHelper::DidNavigateMainFrame(
     const content::LoadCommittedDetails& details,
     const content::FrameNavigateParams& params) {
   if (IsCacheableNTP(web_contents_)) {
-    if (details.http_status_code == 204 || details.http_status_code >= 400) {
-      RedirectToLocalNTP();
-      RecordCacheableNTPLoadHistogram(false);
-      return;
-    }
-    RecordCacheableNTPLoadHistogram(true);
+    UMA_HISTOGRAM_ENUMERATION("InstantExtended.CacheableNTPLoad",
+                              chrome::CACHEABLE_NTP_LOAD_SUCCEEDED,
+                              chrome::CACHEABLE_NTP_LOAD_MAX);
   }
 
   // Always set the title on the new tab page to be the one from our UI
   // resources. Normally, we set the title when we begin a NTP load, but it can
   // get reset in several places (like when you press Reload). This check
   // ensures that the title is properly set to the string defined by the Chrome
   // UI language (rather than the server language) in all cases.
   //
   // We only override the title when it's nonempty to allow the page to set the
   // title if it really wants. An empty title means to use the default. There's
   // also a race condition between this code and the page's SetTitle call which
   // this rule avoids.
   content::NavigationEntry* entry =
       web_contents_->GetController().GetLastCommittedEntry();
   if (entry && entry->GetTitle().empty() &&
       (entry->GetVirtualURL() == GURL(chrome::kChromeUINewTabURL) ||
        chrome::NavEntryIsInstantNTP(web_contents_, entry))) {
     entry->SetTitle(l10n_util::GetStringUTF16(IDS_NEW_TAB_TITLE));
   }
 }
 
-void SearchTabHelper::DidFailProvisionalLoad(
-    content::RenderFrameHost* render_frame_host,
-    const GURL& validated_url,
-    int error_code,
-    const base::string16& /* error_description */) {
-  // If error_code is ERR_ABORTED means that the user has canceled this
-  // navigation so it shouldn't be redirected.
-  if (!render_frame_host->GetParent() && error_code != net::ERR_ABORTED &&
-      validated_url != GURL(chrome::kChromeSearchLocalNtpUrl) &&
-      chrome::IsNTPURL(validated_url, profile())) {
-    RedirectToLocalNTP();
-    RecordCacheableNTPLoadHistogram(false);
-  }
-}
-
 void SearchTabHelper::DidFinishLoad(content::RenderFrameHost* render_frame_host,
                                     const GURL& /* validated_url */) {
   if (!render_frame_host->GetParent()) {
     if (chrome::IsInstantNTP(web_contents_))
       RecordNewTabLoadTime(web_contents_);
 
     DetermineIfPageSupportsInstant();
   }
 }
 
@@ skipping 246 matching lines @@
     InstantSupportChanged(true);
   } else {
     ipc_router_.DetermineIfPageSupportsInstant();
   }
 }
 
 Profile* SearchTabHelper::profile() const {
   return Profile::FromBrowserContext(web_contents_->GetBrowserContext());
 }
 
-void SearchTabHelper::RedirectToLocalNTP() {
-  // Extra parentheses to declare a variable.
-  content::NavigationController::LoadURLParams load_params(
-      (GURL(chrome::kChromeSearchLocalNtpUrl)));
-  load_params.referrer = content::Referrer();
-  load_params.transition_type = ui::PAGE_TRANSITION_SERVER_REDIRECT;
-  // Don't push a history entry.
-  load_params.should_replace_current_entry = true;
-  web_contents_->GetController().LoadURLWithParams(load_params);
-}
-
 bool SearchTabHelper::IsInputInProgress() const {
   OmniboxView* omnibox = GetOmniboxView();
   return !model_.mode().is_ntp() && omnibox &&
       omnibox->model()->focus_state() == OMNIBOX_FOCUS_VISIBLE;
 }
 
 OmniboxView* SearchTabHelper::GetOmniboxView() const {
   return delegate_ ? delegate_->GetOmniboxView() : NULL;
 }