Revert 74292 - Splits ChromeURLDataManager into 2 chunks:...

chrome/browser/browser_about_handler.cc

 // Copyright (c) 2011 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/browser_about_handler.h"
 
 #include <algorithm>
 #include <string>
 #include <vector>
 
@@ skipping 142 matching lines @@
   kVersionPath,
 #if defined(OS_LINUX)
   kSandboxPath,
 #endif
 #if defined(OS_CHROMEOS)
   kNetworkPath,
   kOSCreditsPath,
 #endif
   };
 
+// Points to the singleton AboutSource object, if any.
+ChromeURLDataManager::DataSource* about_source = NULL;
+
 // When you type about:memory, it actually loads an intermediate URL that
 // redirects you to the final page. This avoids the problem where typing
 // "about:memory" on the new tab page or any other page where a process
 // transition would occur to the about URL will cause some confusion.
 //
 // The problem is that during the processing of the memory page, there are two
 // processes active, the original and the destination one. This can create the
 // impression that we're using more resources than we actually are. This
 // redirect solves the problem by eliminating the process transition during the
 // time that about memory is being computed.
@@ skipping 509 matching lines @@
 std::string VersionNumberToString(uint32 value) {
   int hi = (value >> 8) & 0xff;
   int low = value & 0xff;
   return base::IntToString(hi) + "." + base::IntToString(low);
 }
 
 // AboutSource -----------------------------------------------------------------
 
 AboutSource::AboutSource()
     : DataSource(chrome::kAboutScheme, MessageLoop::current()) {
+  // This should be a singleton.
+  DCHECK(!about_source);
+  about_source = this;
+
+  // Add us to the global URL handler on the IO thread.
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      NewRunnableMethod(
+          ChromeURLDataManager::GetInstance(),
+          &ChromeURLDataManager::AddDataSource,
+          make_scoped_refptr(this)));
 }
 
 AboutSource::~AboutSource() {
+  about_source = NULL;
 }
 
 void AboutSource::StartDataRequest(const std::string& path_raw,
     bool is_off_the_record, int request_id) {
   std::string path = path_raw;
   std::string info;
   if (path.find("/") != std::string::npos) {
     size_t pos = path.find("/");
     info = path.substr(pos + 1, path.length() - (pos + 1));
     path = path.substr(0, pos);
@@ skipping 327 matching lines @@
     GpuProcessHostUIShim::GetInstance()->SendAboutGpuHang();
     return true;
   }
 
   // There are a few about: URLs that we hand over to the renderer. If the
   // renderer wants them, don't do any rewriting.
   if (chrome_about_handler::WillHandle(*url))
     return false;
 
   // Anything else requires our special handler; make sure it's initialized.
-  InitializeAboutDataSource(profile);
+  InitializeAboutDataSource();
 
   // Special case about:memory to go through a redirect before ending up on
   // the final page. See GetAboutMemoryRedirectResponse above for why.
   if (LowerCaseEqualsASCII(url->path(), kMemoryPath)) {
     *url = GURL("chrome://about/memory-redirect");
     return true;
   }
 
   // Rewrite the about URL to use chrome:. WebKit treats all about URLS the
   // same (blank page), so if we want to display content, we need another
   // scheme.
   std::string about_url = "chrome://about/";
   about_url.append(url->path());
   *url = GURL(about_url);
   return true;
 }
 
-void InitializeAboutDataSource(Profile* profile) {
-  profile->GetChromeURLDataManager()->AddDataSource(new AboutSource());
+void InitializeAboutDataSource() {
+  // We only need to register the AboutSource once and it is kept globally.
+  // There is currently no way to remove a data source.
+  static bool initialized = false;
+  if (!initialized) {
+    about_source = new AboutSource();
+    initialized = true;
+  }
 }
 
 // This function gets called with the fixed-up chrome: URLs, so we have to
 // compare against those instead of "about:blah".
 bool HandleNonNavigationAboutURL(const GURL& url) {
   // about:ipc is currently buggy, so we disable it for official builds.
 #if !defined(OFFICIAL_BUILD)
 
 #if (defined(OS_MACOSX) || defined(OS_WIN)) && defined(IPC_MESSAGE_LOG_ENABLED)
   if (LowerCaseEqualsASCII(url.spec(), chrome::kChromeUIIPCURL)) {
     // Run the dialog. This will re-use the existing one if it's already up.
     browser::ShowAboutIPCDialog();
     return true;
   }
 #endif
 
 #endif  // OFFICIAL_BUILD
 
   return false;
 }