Introduce ActiveScriptController; track active extension scripts

chrome/browser/extensions/active_script_controller.cc

+// Copyright 2014 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/extensions/active_script_controller.h"
+
+#include "base/metrics/histogram.h"
+#include "chrome/browser/extensions/extension_action.h"
+#include "chrome/common/extensions/api/extension_action/action_info.h"
+#include "content/public/browser/navigation_controller.h"
+#include "content/public/browser/navigation_entry.h"
+#include "content/public/browser/web_contents.h"
+#include "extensions/browser/extension_registry.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/extension_messages.h"
+#include "extensions/common/extension_set.h"
+#include "extensions/common/feature_switch.h"
+#include "extensions/common/permissions/permissions_data.h"
+#include "ipc/ipc_message_macros.h"
+
+namespace extensions {
+
+namespace {
+
+void LogActiveScriptUMA(size_t number_of_active_scripts) {
+  UMA_HISTOGRAM_COUNTS_100(
+      "Extensions.ActiveScriptController.ShownActiveScriptsOnPage",
+      number_of_active_scripts);
+}
+
+}
+
+ActiveScriptController::ActiveScriptController(
+    content::WebContents* web_contents)
+    : content::WebContentsObserver(web_contents),
+      web_contents_(web_contents),

[not at google - send to devlin, 2014/05/08 23:33:19]

WebContentsObserver has a web_contents() method, use that rather than hanging
onto web_contents_ yourself.

[Devlin, 2014/05/09 00:15:32]

Done.

+      enabled_(FeatureSwitch::scripts_require_action()->IsEnabled()) {
+  LOG(WARNING) << "Constructed";

[not at google - send to devlin, 2014/05/08 23:33:19]

remove this

[Devlin, 2014/05/09 00:15:32]

D'oh, missed that one. Thanks.

+}
+
+ActiveScriptController::~ActiveScriptController() {
+  LogActiveScriptUMA(extensions_executing_scripts_.size());
+}
+
+void ActiveScriptController::NotifyScriptExecuting(
+    const std::string& extension_id, int page_id) {
+  if (extensions_executing_scripts_.count(extension_id) ||
+      web_contents_->GetController().GetVisibleEntry()->GetPageID()
+          != page_id) {
+    return;
+  }
+
+  const Extension* extension =
+      ExtensionRegistry::Get(web_contents_->GetBrowserContext())
+          ->enabled_extensions().GetByID(extension_id);
+  if (extension &&
+      PermissionsData::RequiresActionForScriptExecution(extension)) {
+    extensions_executing_scripts_.insert(extension_id);
+    LocationBarController::NotifyChange(web_contents_);
+  }
+}
+
+void ActiveScriptController::OnAdInjectionDetected(
+    const std::string& extension_id) {
+  UMA_HISTOGRAM_BOOLEAN(

[not at google - send to devlin, 2014/05/08 23:33:19]

a couple of problems here:
- it would be useful to know a number here, rather than just a heap of
true/false
- I'm not confident that |extensions_executing_scripts_| hasn't already been
deleted by this point.

a couple of fixes:
- stream extension IDs to this method instead of telling it at the end
- pass in the set/vector of extension IDs all at once and hold onto those IDs
until the next page loads

[Devlin, 2014/05/09 00:15:32]

Can't stream because we can't get a web contents (without changing a bunch of
code).  But, in theory, the order is right. ActivityLog does stuff, and then
ActiveScriptController does stuff.  If we get an overwhelming amount of zeros,
we'll know something went wrong.

+      "ExtensionActivity.AdInjectionCouldHaveBeenStopped",
+      extensions_executing_scripts_.count(extension_id) > 0);
+}
+
+ExtensionAction* ActiveScriptController::GetActionForExtension(
+    const Extension* extension) {
+  if (!enabled_ || extensions_executing_scripts_.count(extension->id()) == 0)
+    return NULL;  // No action for this extension.
+
+  ActiveScriptMap::iterator existing =
+      active_script_actions_.find(extension->id());
+  if (existing != active_script_actions_.end())
+    return existing->second.get();
+
+  linked_ptr<ExtensionAction> action(
+      new ExtensionAction(extension->id(),
+                          ActionInfo::TYPE_PAGE,
+                          ActionInfo()));
+  action->SetTitle(ExtensionAction::kDefaultTabId, extension->name());
+  action->SetIsVisible(ExtensionAction::kDefaultTabId, true);
+
+  const ActionInfo* action_info = ActionInfo::GetPageActionInfo(extension);
+  if (!action_info)
+    action_info = ActionInfo::GetBrowserActionInfo(extension);
+
+  if (action_info && !action_info->default_icon.empty()) {
+    action->set_default_icon(
+        make_scoped_ptr(new ExtensionIconSet(action_info->default_icon)));
+  }
+
+  active_script_actions_[extension->id()] = action;
+  return action.get();
+}
+
+LocationBarController::Action ActiveScriptController::OnClicked(
+    const Extension* extension) {
+  DCHECK(extensions_executing_scripts_.count(extension->id()) > 0);
+  return LocationBarController::ACTION_NONE;
+}
+
+void ActiveScriptController::OnNavigated() {
+  LogActiveScriptUMA(extensions_executing_scripts_.size());
+  extensions_executing_scripts_.clear();
+}
+
+bool ActiveScriptController::OnMessageReceived(const IPC::Message& message) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(ActiveScriptController, message)
+    IPC_MESSAGE_HANDLER(ExtensionHostMsg_NotifyExtensionScriptExecution,
+                        OnNotifyExtensionScriptExecution)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  return handled;
+}
+
+void ActiveScriptController::OnNotifyExtensionScriptExecution(
+    const std::string& extension_id,
+    int page_id) {
+  if (!Extension::IdIsValid(extension_id)) {
+    NOTREACHED();

[not at google - send to devlin, 2014/05/08 23:33:19]

<< "\"" << extension_id << "\" is not a valid ID";

[Devlin, 2014/05/09 00:15:32]

Done.

+    return;
+  }
+  NotifyScriptExecuting(extension_id, page_id);
+}
+
+}  // namespace extensions