Upstream support for WebKit shared timer toggling.

chrome/browser/android/process_utils.cc

Index: chrome/browser/android/process_utils.cc
diff --git a/chrome/browser/android/process_utils.cc b/chrome/browser/android/process_utils.cc
new file mode 100644
index 0000000000000000000000000000000000000000..79d967b1deb5398c8561c88db7ca9cdb10da9b49
--- /dev/null
+++ b/chrome/browser/android/process_utils.cc
@@ -0,0 +1,60 @@
+// Copyright (c) 2012 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/android/process_utils.h"
+
+#include <vector>
+
+#include "base/lazy_instance.h"
+#include "base/logging.h"
+#include "chrome/common/render_messages.h"
+#include "content/public/browser/render_process_host.h"
+#include "jni/process_utils_jni.h"
+
+namespace {
+
+// Only accessed from the JNI thread by ToggleWebKitSharedTimers() which is
+// implemented below.
+base::LazyInstance<std::vector<int /* process id */> > g_suspended_processes =
+    LAZY_INSTANCE_INITIALIZER;
+
+// Suspends timers in all current render processes.
+void SuspendWebKitSharedTimers(std::vector<int>* suspended_processes) {
+  for (content::RenderProcessHost::iterator i(
+          content::RenderProcessHost::AllHostsIterator());
+       !i.IsAtEnd(); i.Advance()) {
+    content::RenderProcessHost* host = i.GetCurrentValue();
+    suspended_processes->push_back(host->GetID());
+    host->Send(new ChromeViewMsg_ToggleWebKitSharedTimer(true));
+  }
+}
+
+void ResumeWebkitSharedTimers(const std::vector<int>& suspended_processes) {
+  for (std::vector<int>::const_iterator it = suspended_processes.begin();
+       it != suspended_processes.end(); ++it) {
+    content::RenderProcessHost* host = content::RenderProcessHost::FromID(*it);
+    if (host)
+      host->Send(new ChromeViewMsg_ToggleWebKitSharedTimer(false));
+  }
+}
+
+}  // namespace
+
+static void ToggleWebKitSharedTimers(JNIEnv* env,
+                                     jclass obj,
+                                     jboolean suspend) {
+  std::vector<int>* suspended_processes = &g_suspended_processes.Get();
+  if (suspend) {
+    DCHECK(suspended_processes->empty());
+    SuspendWebKitSharedTimers(suspended_processes);
+  } else {
+    ResumeWebkitSharedTimers(*suspended_processes);
+    suspended_processes->clear();
+  }
+}
+
+// TODO(pliard): http://crbug.com/137674
+bool RegisterProcessUtils(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}