Forward handling of low-mem message to the content renderer client. Add APIs to handle this case.

chrome/renderer/chrome_content_renderer_client.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/renderer/chrome_content_renderer_client.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/message_loop.h"
 #include "base/metrics/histogram.h"
 #include "base/path_service.h"
 #include "base/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/common/child_process_logging.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/external_ipc_fuzzer.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_constants.h"
 #include "chrome/common/extensions/extension_set.h"
 #include "chrome/common/jstemplate_builder.h"
+#include "content/common/notification_details.h"
+#include "content/common/notification_service.h"
+#include "content/common/notification_source.h"
 #include "chrome/common/render_messages.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/autofill/autofill_agent.h"
 #include "chrome/renderer/autofill/form_manager.h"
 #include "chrome/renderer/autofill/password_autofill_manager.h"
 #include "chrome/renderer/automation/automation_renderer_helper.h"
 #include "chrome/renderer/automation/dom_automation_v8_extension.h"
 #include "chrome/renderer/blocked_plugin.h"
 #include "chrome/renderer/chrome_ppapi_interfaces.h"
 #include "chrome/renderer/chrome_render_process_observer.h"
@@ skipping 164 matching lines @@
 
   WebString dev_tools_scheme(ASCIIToUTF16(chrome::kChromeDevToolsScheme));
   WebSecurityPolicy::registerURLSchemeAsDisplayIsolated(dev_tools_scheme);
 
   WebString internal_scheme(ASCIIToUTF16(chrome::kChromeInternalScheme));
   WebSecurityPolicy::registerURLSchemeAsDisplayIsolated(internal_scheme);
 
   // chrome-extension: resources shouldn't trigger insecure content warnings.
   WebString extension_scheme(ASCIIToUTF16(chrome::kExtensionScheme));
   WebSecurityPolicy::registerURLSchemeAsSecure(extension_scheme);
+
+  // Get updates when we need to purge memory.
+  registrar_.Add(this, content::NOTIFICATION_PURGE_MEMORY, Source<void>(NULL));
 }
 
 void ChromeContentRendererClient::RenderViewCreated(RenderView* render_view) {
   ContentSettingsObserver* content_settings =
       new ContentSettingsObserver(render_view);
   new DevToolsAgent(render_view);
   new ExtensionHelper(render_view, extension_dispatcher_.get());
   new PageLoadHistograms(render_view, histogram_snapshots_.get());
   new PrintWebViewHelper(render_view);
   new SearchBox(render_view);
-  new SpellCheckProvider(render_view, spellcheck_.get());
+  spellcheck_provider_.reset(new SpellCheckProvider(render_view,
+                                                    spellcheck_.get()));
 #if defined(ENABLE_SAFE_BROWSING)
   safe_browsing::MalwareDOMDetails::Create(render_view);
 #endif
 
 #if defined(OS_MACOSX)
   new TextInputClientObserver(render_view);
 #endif  // defined(OS_MACOSX)
 
   PasswordAutofillManager* password_autofill_manager =
       new PasswordAutofillManager(render_view);
@@ skipping 389 matching lines @@
   // uninstalled.
   if (old_url == new_url) {
     bool is_extension_url = !!extensions->GetByURL(new_url);
     if (is_extension_url != extension_dispatcher_->is_extension_process())
       return true;
   }
 
   return !extensions->InSameExtent(old_url, new_url);
 }
 
+void ChromeContentRendererClient::Observe(int type,
+                                          const NotificationSource& source,
+                                          const NotificationDetails& details) {
+  if (type == content::NOTIFICATION_PURGE_MEMORY)
+    ResetSpellCheck();
+}
+
+void ChromeContentRendererClient::ResetSpellCheck() {
+  LOG(INFO) << "Resetting spellcheck in renderer client";
+  RenderThread* thread = RenderThread::current();
+  if (spellcheck_.get())
+    thread->RemoveObserver(spellcheck_.get());
+  spellcheck_.reset(new SpellCheck());
+  thread->AddObserver(spellcheck_.get());
+  if (spellcheck_provider_.get())
+    spellcheck_provider_->SetSpellCheck(spellcheck_.get());
+}
+
 }  // namespace chrome