Implement renderer importance API for WebView

android_webview/native/aw_renderer_priority_manager.cc

+// Copyright 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 "android_webview/native/aw_renderer_priority_manager.h"
+
+#include "base/android/jni_android.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/browser/render_process_host.h"
+#include "jni/AwRendererPriorityManager_jni.h"
+
+namespace android_webview {
+
+AwRendererPriorityManager::AwRendererPriorityManager(
+    content::RenderProcessHost* host)
+    : host_(host), renderer_priority_(RENDERER_PRIORITY_INITIAL) {}
+
+void AwRendererPriorityManager::SetRendererPriority(
+    RendererPriority renderer_priority) {
+  if (host_->GetHandle() == 0) {
+    return;
+  }
+  if (renderer_priority_ != renderer_priority) {
+    renderer_priority_ = renderer_priority;
+    content::BrowserThread::PostTask(
+        content::BrowserThread::PROCESS_LAUNCHER, FROM_HERE,
+        base::Bind(&SetRendererPriorityOnLauncherThread, host_->GetHandle(),
+                   renderer_priority_));
+  }
+}
+
+// static
+void AwRendererPriorityManager::SetRendererPriorityOnLauncherThread(
+    int pid,
+    RendererPriority renderer_priority) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  DCHECK(env);
+  Java_AwRendererPriorityManager_setRendererPriority(
+      env, static_cast<jint>(pid), static_cast<jint>(renderer_priority));
+}
+
+}  // namespace android_webview