Add new user script injection point "document_idle" and make it the default.

Semantically, document-idle means "when the DOM is ready and layout has been idle for awhile", or more loosely, "as soon as we get around to it".

Right now this uses a simple heuristic. It injects scripts 200ms after DOMContentLoaded, or immediately after onload, whichever happens first.

BUG=26126
TEST=Manual. Extensions with content scripts should work.

Review URL: http://codereview.chromium.org/339064

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@30784 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 47 insertions, 0 deletions

diff --git a/chrome/renderer/user_script_idle_scheduler.cc b/chrome/renderer/user_script_idle_scheduler.cc
new file mode 100644
index 0000000..2468bf1
--- /dev/null
+++ b/chrome/renderer/user_script_idle_scheduler.cc
@@ -0,0 +1,47 @@
+// Copyright (c) 2009 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/user_script_idle_scheduler.h"
+
+#include "base/message_loop.h"
+#include "chrome/renderer/render_view.h"
+
+namespace {
+// The length of time to wait after the DOM is complete to try and run user
+// scripts.
+const int kUserScriptIdleTimeoutMs = 200;
+}
+
+UserScriptIdleScheduler::UserScriptIdleScheduler(RenderView* view,
+                                                 WebKit::WebFrame* frame)
+    : ALLOW_THIS_IN_INITIALIZER_LIST(method_factory_(this)), view_(view),
+  frame_(frame), has_run_(false) {
+}
+
+void UserScriptIdleScheduler::DidFinishDocumentLoad() {
+  MessageLoop::current()->PostDelayedTask(FROM_HERE,
+      method_factory_.NewRunnableMethod(&UserScriptIdleScheduler::MaybeRun),
+      kUserScriptIdleTimeoutMs);
+}
+
+void UserScriptIdleScheduler::DidFinishLoad() {
+  // Ensure that running scripts does not keep any progress UI running.
+  MessageLoop::current()->PostTask(FROM_HERE,
+      method_factory_.NewRunnableMethod(&UserScriptIdleScheduler::MaybeRun));
+}
+
+void UserScriptIdleScheduler::Cancel() {
+  view_ = NULL;
+  frame_ = NULL;
+}
+
+void UserScriptIdleScheduler::MaybeRun() {
+  if (!view_)
+    return;
+
+  DCHECK(frame_);
+  view_->OnUserScriptIdleTriggered(frame_);
+  Cancel();
+  has_run_ = true;
+}