Allow webRequest API extensions to clear the in-memory cache of WebKit.

If the behavior of a webRequest API extension changes (i.e. different URLs are blocked) this effect was not visible instantly due to WebKit's in-memory cache. This CL introduces a means to clear the cache.

BUG=94284
TEST=no


Review URL: http://codereview.chromium.org/7835031

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@103289 0039d316-1c4b-4281-b951-d872f2087c98

14 files changed, 226 insertions, 14 deletions

diff --git a/chrome/browser/extensions/extension_function_dispatcher.cc b/chrome/browser/extensions/extension_function_dispatcher.cc
index 619d841..9d7b435 100644
--- a/chrome/browser/extensions/extension_function_dispatcher.cc
+++ b/chrome/browser/extensions/extension_function_dispatcher.cc
@@ -361,6 +361,7 @@ void FactoryRegistry::ResetFunctions() {
   // WebRequest.
   RegisterFunction<WebRequestAddEventListener>();
   RegisterFunction<WebRequestEventHandled>();
+  RegisterFunction<WebRequestHandlerBehaviorChanged>();
 
   // Preferences.
   RegisterFunction<GetPreferenceFunction>();
diff --git a/chrome/browser/extensions/extension_webrequest_api.cc b/chrome/browser/extensions/extension_webrequest_api.cc
index cf13a52..1e80edd 100644
--- a/chrome/browser/extensions/extension_webrequest_api.cc
+++ b/chrome/browser/extensions/extension_webrequest_api.cc
@@ -20,6 +20,7 @@
 #include "chrome/browser/extensions/extension_webrequest_time_tracker.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/renderer_host/chrome_render_message_filter.h"
+#include "chrome/browser/renderer_host/web_cache_manager.h"
 #include "chrome/common/extensions/extension.h"
 #include "chrome/common/extensions/extension_error_utils.h"
 #include "chrome/common/extensions/url_pattern.h"
@@ -1498,3 +1499,8 @@ bool WebRequestEventHandled::RunImpl() {
 
   return true;
 }
+
+bool WebRequestHandlerBehaviorChanged::RunImpl() {
+  WebCacheManager::GetInstance()->ClearCacheOnNavigation();
+  return true;
+}
diff --git a/chrome/browser/extensions/extension_webrequest_api.h b/chrome/browser/extensions/extension_webrequest_api.h
index f44d5b7..8a131c0 100644
--- a/chrome/browser/extensions/extension_webrequest_api.h
+++ b/chrome/browser/extensions/extension_webrequest_api.h
@@ -370,4 +370,11 @@ class WebRequestEventHandled : public SyncIOThreadExtensionFunction {
   DECLARE_EXTENSION_FUNCTION_NAME("experimental.webRequest.eventHandled");
 };
 
+class WebRequestHandlerBehaviorChanged : public AsyncExtensionFunction {
+ public:
+  virtual bool RunImpl();
+  DECLARE_EXTENSION_FUNCTION_NAME(
+      "experimental.webRequest.handlerBehaviorChanged");
+};
+
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_WEBREQUEST_API_H_
diff --git a/chrome/browser/renderer_host/web_cache_manager.cc b/chrome/browser/renderer_host/web_cache_manager.cc
index 5a3a0ff..8ee268d 100644
--- a/chrome/browser/renderer_host/web_cache_manager.cc
+++ b/chrome/browser/renderer_host/web_cache_manager.cc
@@ -146,8 +146,15 @@ void WebCacheManager::SetGlobalSizeLimit(size_t bytes) {
 
 void WebCacheManager::ClearCache() {
   // Tell each renderer process to clear the cache.
-  ClearRendederCache(active_renderers_);
-  ClearRendederCache(inactive_renderers_);
+  ClearRendederCache(active_renderers_, INSTANTLY);
+  ClearRendederCache(inactive_renderers_, INSTANTLY);
+}
+
+void WebCacheManager::ClearCacheOnNavigation() {
+  // Tell each renderer process to clear the cache when a tab is reloaded or
+  // the user navigates to a new website.
+  ClearRendederCache(active_renderers_, ON_NAVIGATION);
+  ClearRendederCache(inactive_renderers_, ON_NAVIGATION);
 }
 
 void WebCacheManager::Observe(int type,
@@ -321,12 +328,14 @@ void WebCacheManager::EnactStrategy(const AllocationStrategy& strategy) {
   }
 }
 
-void WebCacheManager::ClearRendederCache(const std::set<int>& renderers) {
+void WebCacheManager::ClearRendederCache(
+    const std::set<int>& renderers,
+    WebCacheManager::ClearCacheOccasion occasion) {
   std::set<int>::const_iterator iter = renderers.begin();
   for (; iter != renderers.end(); ++iter) {
     RenderProcessHost* host = RenderProcessHost::FromID(*iter);
     if (host)
-      host->Send(new ChromeViewMsg_ClearCache());
+      host->Send(new ChromeViewMsg_ClearCache(occasion == ON_NAVIGATION));
   }
 }
 
diff --git a/chrome/browser/renderer_host/web_cache_manager.h b/chrome/browser/renderer_host/web_cache_manager.h
index 02c6958..0006572 100644
--- a/chrome/browser/renderer_host/web_cache_manager.h
+++ b/chrome/browser/renderer_host/web_cache_manager.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2009 The Chromium Authors. All rights reserved.
+// 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.
 
@@ -70,6 +70,10 @@ class WebCacheManager : public NotificationObserver {
   // Clears all in-memory caches.
   void ClearCache();
 
+  // Clears all in-memory caches when a tab is reloaded or the user navigates
+  // to a different website.
+  void ClearCacheOnNavigation();
+
   // NotificationObserver implementation:
   virtual void Observe(int type,
                        const NotificationSource& source,
@@ -179,8 +183,17 @@ class WebCacheManager : public NotificationObserver {
   // allocations according to |strategy|.
   void EnactStrategy(const AllocationStrategy& strategy);
 
+  enum ClearCacheOccasion {
+    // Instructs to clear the cache instantly.
+    INSTANTLY,
+    // Instructs to clear the cache when a navigation takes place (this
+    // includes reloading a tab).
+    ON_NAVIGATION
+  };
+
   // Inform all |renderers| to clear their cache.
-  void ClearRendederCache(const std::set<int>& renderers);
+  void ClearRendederCache(const std::set<int>& renderers,
+                          ClearCacheOccasion occation);
 
   // Check to see if any active renderers have fallen inactive.
   void FindInactiveRenderers();
diff --git a/chrome/common/extensions/api/extension_api.json b/chrome/common/extensions/api/extension_api.json
index 4f4077a..a0e91fe8 100644
--- a/chrome/common/extensions/api/extension_api.json
+++ b/chrome/common/extensions/api/extension_api.json
@@ -5704,6 +5704,14 @@
             "name": "response"
           }
         ]
+      },
+      {
+        "name": "handlerBehaviorChanged",
+        "type": "function",
+        "description": "Needs to be called when the behavior of the webRequest handlers has changed to prevent incorrect handling due to caching. This function call is expensive. Don't call it often.",
+        "parameters": [
+          {"type": "function", "name": "callback", "optional": true, "parameters": []}
+        ]
       }
     ],
     "events": [
diff --git a/chrome/common/extensions/docs/experimental.webRequest.html b/chrome/common/extensions/docs/experimental.webRequest.html
index 6b0847e..7b1f2cd 100644
--- a/chrome/common/extensions/docs/experimental.webRequest.html
+++ b/chrome/common/extensions/docs/experimental.webRequest.html
@@ -319,6 +319,8 @@
                         <a href="#method-anchor">methodName</a>
                       </li><li style="display: none; ">
                         <a href="#method-anchor">methodName</a>
+                      </li><li>
+                        <a href="#method-handlerBehaviorChanged">handlerBehaviorChanged</a>
                       </li>
                     </ol>
                   </li>
@@ -806,6 +808,137 @@ chrome.windows.onRemoved.addListener(
                 </p>
               </div> <!-- /description -->
 
+            </div><div class="apiItem">
+              <a name="method-handlerBehaviorChanged"></a> <!-- method-anchor -->
+              <h4>handlerBehaviorChanged</h4>
+
+              <div class="summary"><span style="display: none; ">void</span>
+                  <!-- Note: intentionally longer 80 columns -->
+                  <span>chrome.experimental.webRequest.handlerBehaviorChanged</span>(<span class="optional"><span style="display: none; ">, </span><span>function</span>
+                      <var><span>callback</span></var></span>)</div>
+
+              <div class="description">
+                <p class="todo" style="display: none; ">Undocumented.</p>
+                <p>Needs to be called when the behavior of the webRequest handlers has changed to prevent incorrect handling due to caching. This function call is expensive. Don't call it often.</p>
+
+                <!-- PARAMETERS -->
+                <h4>Parameters</h4>
+                <dl>
+                  <div>
+                    <div>
+          <dt>
+            <var>callback</var>
+              <em>
+
+                <!-- TYPE -->
+                <div style="display:inline">
+                  (
+                    <span class="optional">optional</span>
+                    <span class="enum" style="display: none; ">enumerated</span>
+                    <span id="typeTemplate">
+                      <span style="display: none; ">
+                        <a> Type</a>
+                      </span>
+                      <span>
+                        <span style="display: none; ">
+                          array of <span><span></span></span>
+                        </span>
+                        <span>function</span>
+                        <span style="display: none; "></span>
+                      </span>
+                    </span>
+                  )
+                </div>
+
+              </em>
+          </dt>
+          <dd class="todo">
+            Undocumented.
+          </dd>
+          <dd style="display: none; ">
+            Description of this parameter from the json schema.
+          </dd>
+          <dd style="display: none; ">
+            This parameter was added in version
+            <b><span></span></b>.
+            You must omit this parameter in earlier versions,
+            and you may omit it in any version.  If you require this
+            parameter, the manifest key
+            <a href="manifest.html#minimum_chrome_version">minimum_chrome_version</a>
+            can ensure that your extension won't be run in an earlier browser version.
+          </dd>
+
+          <!-- OBJECT PROPERTIES -->
+          <dd style="display: none; ">
+            <dl>
+              <div>
+                <div>
+                </div>
+              </div>
+            </dl>
+          </dd>
+
+          <!-- OBJECT METHODS -->
+          <dd style="display: none; ">
+            <div></div>
+          </dd>
+
+          <!-- OBJECT EVENT FIELDS -->
+          <dd style="display: none; ">
+            <div></div>
+          </dd>
+
+          <!-- FUNCTION PARAMETERS -->
+          <dd style="display: none; ">
+            <div></div>
+          </dd>
+
+        </div>
+                  </div>
+                </dl>
+
+                <!-- RETURNS -->
+                <h4 style="display: none; ">Returns</h4>
+                <dl>
+                  <div style="display: none; ">
+                    <div>
+                    </div>
+                  </div>
+                </dl>
+
+                <!-- CALLBACK -->
+                <div>
+                  <div>
+                  <h4>Callback function</h4>
+                  <p style="display: none; ">
+                    The callback <em>parameter</em> should specify a function
+                    that looks like this:
+                  </p>
+                  <p>
+                    If you specify the <em>callback</em> parameter, it should
+                    specify a function that looks like this:
+                  </p>
+
+                  <!-- Note: intentionally longer 80 columns -->
+                  <pre>function(<span></span>) <span class="subdued">{...}</span>;</pre>
+                  <dl>
+                    <div style="display: none; ">
+                      <div>
+                      </div>
+                    </div>
+                  </dl>
+                  </div>
+                </div>
+
+                <!-- MIN_VERSION -->
+                <p style="display: none; ">
+                  This function was added in version <b><span></span></b>.
+                  If you require this function, the manifest key
+                  <a href="manifest.html#minimum_chrome_version">minimum_chrome_version</a>
+                  can ensure that your extension won't be run in an earlier browser version.
+                </p>
+              </div> <!-- /description -->
+
             </div>  <!-- /apiItem -->
 
           </div>  <!-- /apiGroup -->
diff --git a/chrome/common/extensions/docs/samples.json b/chrome/common/extensions/docs/samples.json
index 66f22ed..5614d6d 100644
--- a/chrome/common/extensions/docs/samples.json
+++ b/chrome/common/extensions/docs/samples.json
@@ -89,6 +89,7 @@
     "chrome.experimental.webNavigation.onReferenceFragmentUpdated": "experimental.webNavigation.html#event-onReferenceFragmentUpdated",
     "chrome.experimental.webRequest.addEventListener": "experimental.webRequest.html#method-addEventListener",
     "chrome.experimental.webRequest.eventHandled": "experimental.webRequest.html#method-eventHandled",
+    "chrome.experimental.webRequest.handlerBehaviorChanged": "experimental.webRequest.html#method-handlerBehaviorChanged",
     "chrome.experimental.webRequest.onAuthRequired": "experimental.webRequest.html#event-onAuthRequired",
     "chrome.experimental.webRequest.onBeforeRedirect": "experimental.webRequest.html#event-onBeforeRedirect",
     "chrome.experimental.webRequest.onBeforeRequest": "experimental.webRequest.html#event-onBeforeRequest",
diff --git a/chrome/common/render_messages.h b/chrome/common/render_messages.h
index 7d92fa2..84d1cff 100644
--- a/chrome/common/render_messages.h
+++ b/chrome/common/render_messages.h
@@ -138,7 +138,8 @@ IPC_MESSAGE_CONTROL3(ChromeViewMsg_SetCacheCapacities,
                      size_t /* capacity */)
 
 // Tells the renderer to clear the cache.
-IPC_MESSAGE_CONTROL0(ChromeViewMsg_ClearCache)
+IPC_MESSAGE_CONTROL1(ChromeViewMsg_ClearCache,
+                     bool /* on_navigation */)
 
 // Tells the renderer to dump as much memory as it can, perhaps because we
 // have memory pressure or the renderer is (or will be) paged out.  This
diff --git a/chrome/renderer/chrome_content_renderer_client.cc b/chrome/renderer/chrome_content_renderer_client.cc
index 91841cf..88d41cf 100644
--- a/chrome/renderer/chrome_content_renderer_client.cc
+++ b/chrome/renderer/chrome_content_renderer_client.cc
@@ -243,7 +243,8 @@ void ChromeContentRendererClient::RenderViewCreated(RenderView* render_view) {
 
   TranslateHelper* translate = new TranslateHelper(render_view, autofill_agent);
   new ChromeRenderViewObserver(
-      render_view, content_settings, extension_dispatcher_.get(), translate);
+      render_view, content_settings, chrome_observer_.get(),
+      extension_dispatcher_.get(), translate);
 
   // Used only for testing/automation.
   if (CommandLine::ForCurrentProcess()->HasSwitch(
diff --git a/chrome/renderer/chrome_render_process_observer.cc b/chrome/renderer/chrome_render_process_observer.cc
index 93d1fa8..ad41476 100644
--- a/chrome/renderer/chrome_render_process_observer.cc
+++ b/chrome/renderer/chrome_render_process_observer.cc
@@ -196,7 +196,8 @@ bool ChromeRenderProcessObserver::is_incognito_process_ = false;
 
 ChromeRenderProcessObserver::ChromeRenderProcessObserver(
     chrome::ChromeContentRendererClient* client)
-    : client_(client) {
+    : client_(client),
+      clear_cache_pending_(false) {
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (command_line.HasSwitch(switches::kEnableWatchdog)) {
     // TODO(JAR): Need to implement renderer IO msgloop watchdog.
@@ -314,8 +315,12 @@ void ChromeRenderProcessObserver::OnSetCacheCapacities(size_t min_dead_capacity,
       min_dead_capacity, max_dead_capacity, capacity);
 }
 
-void ChromeRenderProcessObserver::OnClearCache() {
-  WebCache::clear();
+void ChromeRenderProcessObserver::OnClearCache(bool on_navigation) {
+  if (on_navigation) {
+    clear_cache_pending_ = true;
+  } else {
+    WebCache::clear();
+  }
 }
 
 void ChromeRenderProcessObserver::OnGetCacheResourceStats() {
@@ -409,3 +414,10 @@ void ChromeRenderProcessObserver::OnPurgeMemory() {
   if (client_)
     client_->OnPurgeMemory();
 }
+
+void ChromeRenderProcessObserver::ExecutePendingClearCache() {
+  if (clear_cache_pending_) {
+    clear_cache_pending_ = false;
+    WebCache::clear();
+  }
+}
diff --git a/chrome/renderer/chrome_render_process_observer.h b/chrome/renderer/chrome_render_process_observer.h
index 80bf18ef..615b6c3 100644
--- a/chrome/renderer/chrome_render_process_observer.h
+++ b/chrome/renderer/chrome_render_process_observer.h
@@ -33,6 +33,10 @@ class ChromeRenderProcessObserver : public RenderProcessObserver {
 
   static bool is_incognito_process() { return is_incognito_process_; }
 
+  // Needs to be called by RenderViews in case of navigations to execute
+  // any 'clear cache' commands that were delayed until the next navigation.
+  void ExecutePendingClearCache();
+
  private:
   // RenderProcessObserver implementation.
   virtual bool OnControlMessageReceived(const IPC::Message& message) OVERRIDE;
@@ -45,7 +49,9 @@ class ChromeRenderProcessObserver : public RenderProcessObserver {
   void OnSetCacheCapacities(size_t min_dead_capacity,
                             size_t max_dead_capacity,
                             size_t capacity);
-  void OnClearCache();
+  // If |on_navigation| is true, the clearing is delayed until the next
+  // navigation event.
+  void OnClearCache(bool on_navigation);
   void OnGetCacheResourceStats();
   void OnSetFieldTrialGroup(const std::string& fiel_trial_name,
                             const std::string& group_name);
@@ -58,6 +64,8 @@ class ChromeRenderProcessObserver : public RenderProcessObserver {
   static bool is_incognito_process_;
   scoped_ptr<ResourceDispatcherDelegate> resource_delegate_;
   chrome::ChromeContentRendererClient* client_;
+  // If true, the web cache shall be cleared before the next navigation event.
+  bool clear_cache_pending_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeRenderProcessObserver);
 };
diff --git a/chrome/renderer/chrome_render_view_observer.cc b/chrome/renderer/chrome_render_view_observer.cc
index b913137..f4648fbc 100644
--- a/chrome/renderer/chrome_render_view_observer.cc
+++ b/chrome/renderer/chrome_render_view_observer.cc
@@ -16,6 +16,7 @@
 #include "chrome/common/url_constants.h"
 #include "chrome/renderer/about_handler.h"
 #include "chrome/renderer/automation/dom_automation_controller.h"
+#include "chrome/renderer/chrome_render_process_observer.h"
 #include "chrome/renderer/content_settings_observer.h"
 #include "chrome/renderer/extensions/extension_dispatcher.h"
 #include "chrome/renderer/external_host_bindings.h"
@@ -198,11 +199,13 @@ GURL StripRef(const GURL& url) {
 ChromeRenderViewObserver::ChromeRenderViewObserver(
     RenderView* render_view,
     ContentSettingsObserver* content_settings,
+    ChromeRenderProcessObserver* chrome_render_process_observer,
     ExtensionDispatcher* extension_dispatcher,
     TranslateHelper* translate_helper)
     : RenderViewObserver(render_view),
-      content_settings_(content_settings),
+      chrome_render_process_observer_(chrome_render_process_observer),
       extension_dispatcher_(extension_dispatcher),
+      content_settings_(content_settings),
       translate_helper_(translate_helper),
       phishing_classifier_(NULL),
       last_indexed_page_id_(-1),
@@ -336,6 +339,10 @@ void ChromeRenderViewObserver::OnSetAllowRunningInsecureContent(bool allow) {
 }
 
 void ChromeRenderViewObserver::Navigate(const GURL& url) {
+  // Execute cache clear operations that were postponed until a navigation
+  // event (including tab reload).
+  if (chrome_render_process_observer_)
+    chrome_render_process_observer_->ExecutePendingClearCache();
   AboutHandler::MaybeHandle(url);
 }
 
diff --git a/chrome/renderer/chrome_render_view_observer.h b/chrome/renderer/chrome_render_view_observer.h
index fa2946a..cf1497e 100644
--- a/chrome/renderer/chrome_render_view_observer.h
+++ b/chrome/renderer/chrome_render_view_observer.h
@@ -16,6 +16,7 @@
 #include "googleurl/src/gurl.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPermissionClient.h"
 
+class ChromeRenderProcessObserver;
 class ContentSettingsObserver;
 class DomAutomationController;
 class ExtensionDispatcher;
@@ -43,6 +44,7 @@ class ChromeRenderViewObserver : public RenderViewObserver,
   ChromeRenderViewObserver(
       RenderView* render_view,
       ContentSettingsObserver* content_settings,
+      ChromeRenderProcessObserver* chrome_render_process_observer,
       ExtensionDispatcher* extension_dispatcher,
       TranslateHelper* translate_helper);
   virtual ~ChromeRenderViewObserver();
@@ -171,9 +173,12 @@ class ChromeRenderViewObserver : public RenderViewObserver,
   // Save the JavaScript to preload if a ViewMsg_WebUIJavaScript is received.
   scoped_ptr<WebUIJavaScript> webui_javascript_;
 
+  // Owned by ChromeContentRendererClient and outlive us.
+  ChromeRenderProcessObserver* chrome_render_process_observer_;
+  ExtensionDispatcher* extension_dispatcher_;
+
   // Have the same lifetime as us.
   ContentSettingsObserver* content_settings_;
-  ExtensionDispatcher* extension_dispatcher_;
   TranslateHelper* translate_helper_;
   safe_browsing::PhishingClassifierDelegate* phishing_classifier_;