Makes a handful of DataSources not replace the existing

DataSource. In the long term all DataSources should do this, but for
now I've added a method that does it.

I recently added the IsRegistered method thinking registration should
look like:

  if (!contents->profile()->GetChromeURLDataManager()->IsRegistered(
      SomeSource::kSomeName)) {
    contents->profile()->GetChromeURLDataManager()->AddDataSource(
      new SomeSource());
  }

But this is too tedious. And long term we should make all sources
replace the existing one.

BUG=52022
TEST=none

Review URL: http://codereview.chromium.org/6546078

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@75752 0039d316-1c4b-4281-b951-d872f2087c98

10 files changed, 39 insertions, 21 deletions

diff --git a/chrome/browser/sessions/session_restore_uitest.cc b/chrome/browser/sessions/session_restore_uitest.cc
index d79efa5..496f671 100644
--- a/chrome/browser/sessions/session_restore_uitest.cc
+++ b/chrome/browser/sessions/session_restore_uitest.cc
@@ -450,9 +450,7 @@ TEST_F(SessionRestoreUITest, TwoWindowsCloseOneRestoreOnlyOne) {
 // process-per-site and process-per-site-instance, because we treat the new tab
 // as a special case in process-per-site-instance so that it only ever uses one
 // process.)
-//
-// Flaky: http://code.google.com/p/chromium/issues/detail?id=52022
-TEST_F(SessionRestoreUITest, FLAKY_ShareProcessesOnRestore) {
+TEST_F(SessionRestoreUITest, ShareProcessesOnRestore) {
   if (ProxyLauncher::in_process_renderer()) {
     // No point in running this test in single process mode.
     return;
diff --git a/chrome/browser/webui/chrome_url_data_manager.cc b/chrome/browser/webui/chrome_url_data_manager.cc
index c560783..d7abed2 100644
--- a/chrome/browser/webui/chrome_url_data_manager.cc
+++ b/chrome/browser/webui/chrome_url_data_manager.cc
@@ -48,7 +48,6 @@ ChromeURLDataManager::~ChromeURLDataManager() {
 
 void ChromeURLDataManager::AddDataSource(DataSource* source) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  registered_source_names_.insert(source->source_name());
   BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
       NewRunnableFunction(AddDataSourceOnIOThread,
@@ -56,10 +55,6 @@ void ChromeURLDataManager::AddDataSource(DataSource* source) {
                           make_scoped_refptr(source)));
 }
 
-bool ChromeURLDataManager::IsRegistered(const std::string& name) {
-  return registered_source_names_.find(name) != registered_source_names_.end();
-}
-
 // static
 void ChromeURLDataManager::DeleteDataSources() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
@@ -149,6 +144,10 @@ MessageLoop* ChromeURLDataManager::DataSource::MessageLoopForRequestPath(
   return message_loop_;
 }
 
+bool ChromeURLDataManager::DataSource::ShouldReplaceExistingSource() const {
+  return true;
+}
+
 // static
 void ChromeURLDataManager::DataSource::SetFontAndTextDirection(
     DictionaryValue* localized_strings) {
diff --git a/chrome/browser/webui/chrome_url_data_manager.h b/chrome/browser/webui/chrome_url_data_manager.h
index be4cab0..ec77efb 100644
--- a/chrome/browser/webui/chrome_url_data_manager.h
+++ b/chrome/browser/webui/chrome_url_data_manager.h
@@ -6,8 +6,6 @@
 #define CHROME_BROWSER_WEBUI_CHROME_URL_DATA_MANAGER_H_
 #pragma once
 
-#include <map>
-#include <set>
 #include <string>
 
 #include "base/ref_counted.h"
@@ -95,6 +93,15 @@ class ChromeURLDataManager {
 
     const std::string& source_name() const { return source_name_; }
 
+    // Returns true if this DataSource should replace an existing DataSource
+    // with the same name that has already been registered. The default is
+    // true.
+    //
+    // WARNING: this is invoked on the IO thread.
+    //
+    // TODO: nuke this and convert all callers to not replace.
+    virtual bool ShouldReplaceExistingSource() const;
+
     static void SetFontAndTextDirection(DictionaryValue* localized_strings);
 
    protected:
@@ -144,9 +151,6 @@ class ChromeURLDataManager {
   // destructed in the same thread as they are constructed (the UI thread).
   void AddDataSource(DataSource* source);
 
-  // Returns true if a DataSource has been added with the given name.
-  bool IsRegistered(const std::string& name);
-
   // Deletes any data sources no longer referenced. This is normally invoked
   // for you, but can be invoked to force deletion (such as during shutdown).
   static void DeleteDataSources();
@@ -165,12 +169,6 @@ class ChromeURLDataManager {
 
   Profile* profile_;
 
-  // Names of the DataSources that have been registered.
-  // By caching this rather than accessing ChromeURLDataManagerBackend we avoid
-  // a delay between when AddDataSource is invoked and when the IO thread
-  // processes it.
-  std::set<std::string> registered_source_names_;
-
   // Lock used when accessing |data_sources_|.
   static base::Lock delete_lock_;
 
diff --git a/chrome/browser/webui/chrome_url_data_manager_backend.cc b/chrome/browser/webui/chrome_url_data_manager_backend.cc
index fab67db..b49606b 100644
--- a/chrome/browser/webui/chrome_url_data_manager_backend.cc
+++ b/chrome/browser/webui/chrome_url_data_manager_backend.cc
@@ -178,8 +178,11 @@ void ChromeURLDataManagerBackend::AddDataSource(
     ChromeURLDataManager::DataSource* source) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DataSourceMap::iterator i = data_sources_.find(source->source_name());
-  if (i != data_sources_.end())
+  if (i != data_sources_.end()) {
+    if (!source->ShouldReplaceExistingSource())
+      return;
     i->second->backend_ = NULL;
+  }
   data_sources_[source->source_name()] = source;
   source->backend_ = this;
 }
diff --git a/chrome/browser/webui/new_tab_ui.cc b/chrome/browser/webui/new_tab_ui.cc
index 99a5e83..26acf50 100644
--- a/chrome/browser/webui/new_tab_ui.cc
+++ b/chrome/browser/webui/new_tab_ui.cc
@@ -598,3 +598,7 @@ void NewTabUI::NewTabHTMLSource::StartDataRequest(const std::string& path,
 std::string NewTabUI::NewTabHTMLSource::GetMimeType(const std::string&) const {
   return "text/html";
 }
+
+bool NewTabUI::NewTabHTMLSource::ShouldReplaceExistingSource() const {
+  return false;
+}
diff --git a/chrome/browser/webui/new_tab_ui.h b/chrome/browser/webui/new_tab_ui.h
index a627a00..777643b 100644
--- a/chrome/browser/webui/new_tab_ui.h
+++ b/chrome/browser/webui/new_tab_ui.h
@@ -71,6 +71,8 @@ class NewTabUI : public WebUI,
 
     virtual std::string GetMimeType(const std::string&) const;
 
+    virtual bool ShouldReplaceExistingSource() const;
+
     // Setters and getters for first_run.
     static void set_first_run(bool first_run) { first_run_ = first_run; }
     static bool first_run() { return first_run_; }
diff --git a/chrome/browser/webui/web_ui_favicon_source.cc b/chrome/browser/webui/web_ui_favicon_source.cc
index e7f0d06..51e6d87 100644
--- a/chrome/browser/webui/web_ui_favicon_source.cc
+++ b/chrome/browser/webui/web_ui_favicon_source.cc
@@ -54,6 +54,12 @@ std::string WebUIFavIconSource::GetMimeType(const std::string&) const {
   return "image/png";
 }
 
+bool WebUIFavIconSource::ShouldReplaceExistingSource() const {
+  // Leave the existing DataSource in place, otherwise we'll drop any pending
+  // requests on the floor.
+  return false;
+}
+
 void WebUIFavIconSource::OnFavIconDataAvailable(
     FaviconService::Handle request_handle,
     bool know_favicon,
diff --git a/chrome/browser/webui/web_ui_favicon_source.h b/chrome/browser/webui/web_ui_favicon_source.h
index 5a538fa..80f909a 100644
--- a/chrome/browser/webui/web_ui_favicon_source.h
+++ b/chrome/browser/webui/web_ui_favicon_source.h
@@ -30,6 +30,9 @@ class WebUIFavIconSource : public ChromeURLDataManager::DataSource {
 
   virtual std::string GetMimeType(const std::string&) const;
 
+  virtual bool ShouldReplaceExistingSource() const;
+
+ private:
   // Called when favicon data is available from the history backend.
   void OnFavIconDataAvailable(FaviconService::Handle request_handle,
                               bool know_favicon,
@@ -37,7 +40,6 @@ class WebUIFavIconSource : public ChromeURLDataManager::DataSource {
                               bool expired,
                               GURL url);
 
- private:
   // Sends the default favicon.
   void SendDefaultResponse(int request_id);
 
diff --git a/chrome/browser/webui/web_ui_theme_source.cc b/chrome/browser/webui/web_ui_theme_source.cc
index 5a65bdd..1bdbfbe 100644
--- a/chrome/browser/webui/web_ui_theme_source.cc
+++ b/chrome/browser/webui/web_ui_theme_source.cc
@@ -94,6 +94,10 @@ MessageLoop* WebUIThemeSource::MessageLoopForRequestPath(
   return DataSource::MessageLoopForRequestPath(path);
 }
 
+bool WebUIThemeSource::ShouldReplaceExistingSource() const {
+  return false;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 // WebUIThemeSource, private:
 
diff --git a/chrome/browser/webui/web_ui_theme_source.h b/chrome/browser/webui/web_ui_theme_source.h
index 3b1bb82..2f1febf 100644
--- a/chrome/browser/webui/web_ui_theme_source.h
+++ b/chrome/browser/webui/web_ui_theme_source.h
@@ -27,6 +27,8 @@ class WebUIThemeSource : public ChromeURLDataManager::DataSource {
   // Used to tell ChromeURLDataManager which thread to handle the request on.
   virtual MessageLoop* MessageLoopForRequestPath(const std::string& path) const;
 
+  virtual bool ShouldReplaceExistingSource() const;
+
  protected:
   virtual ~WebUIThemeSource();