Added android_browser_process.

content/public/android/java/org/chromium/content/browser/AndroidBrowserProcess.java

+// 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.
+
+package org.chromium.content.browser;
+
+import android.app.ActivityManager;
+import android.content.Context;
+import android.content.res.Resources;
+import android.util.Log;
+
+import org.chromium.content.app.ContentMain;
+import org.chromium.content.browser.ContentView;
+import org.chromium.content.browser.LibraryLoader;
+
+// NOTE: This file hasn't been fully upstreamed, please don't merge to downstream.
+public class AndroidBrowserProcess {
+
+    private static final String TAG = "BrowserProcessMain";
+
+    // Prevents initializing the process more than once.
+    private static boolean sInitialized = false;
+
+    // Computes the actual max renderer processes used.
+    private static int normalizeMaxRendererProcesses(Context context, int maxRendererProcesses) {
+        if (maxRendererProcesses == MAX_RENDERERS_AUTOMATIC) {
+            // We use the device's memory class to decide the maximum renderer
+            // processes. For the baseline devices the memory class is 16 and we will
+            // limit it to one render process. For the devices with memory class 24,
+            // we allow two render processes.
+            ActivityManager am = (ActivityManager)context.getSystemService(
+                    Context.ACTIVITY_SERVICE);
+            maxRendererProcesses = Math.max(((am.getMemoryClass() - 8) / 8), 1);
+        }
+        if (maxRendererProcesses > MAX_RENDERERS_LIMIT) {
+            Log.w(TAG, "Excessive maxRendererProcesses value: " + maxRendererProcesses);
+            return MAX_RENDERERS_LIMIT;
+        }
+        return Math.max(0, maxRendererProcesses);
+    }
+
+    // Automatically decide the number of renderer processes to use based on device memory class.
+    public static final int MAX_RENDERERS_AUTOMATIC = -1;
+    // Use single-process mode that runs the renderer on a separate thread in the main application.
+    public static final int MAX_RENDERERS_SINGLE_PROCESS = 0;
+    // Cap on the maximum number of renderer processes that can be requested.
+    public static final int MAX_RENDERERS_LIMIT = 3;  // TODO(tedbo): Raise limit
+
+    /**
+     * Initialize the process as a ContentView host. This must be called from the main UI thread.
+     * This should be called by the ContentView constructor to prepare this process for ContentView
+     * use outside of the browser. In the case where ContentView is used in the browser then
+     * initBrowserProcess() should already have been called and this is a no-op.
+     *
+     * @param context Context used to obtain the application context.
+     * @param maxRendererProcesses See ContentView.enableMultiProcess().
+     */
+    public static void initContentViewProcess(Context context, int maxRendererProcesses) {
+        genericChromiumProcessInit(context, maxRendererProcesses, false);
+    }
+
+    /**
+     * Initialize the platform browser process. This must be called from the main UI thread before
+     * accessing ContentView in order to treat this as a browser process.
+     *
+     * @param context Context used to obtain the application context.
+     * @param maxRendererProcesses See ContentView.enableMultiProcess().
+     */
+    public static void initChromiumBrowserProcess(Context context, int maxRendererProcesses) {
+        genericChromiumProcessInit(context, maxRendererProcesses, true);
+    }
+
+    /**
+     * Shared implementation for the initXxx methods.
+     * @param context Context used to obtain the application context
+     * @param maxRendererProcesses See ContentView.enableMultiProcess()
+     * @param hostIsChrome pass true if running as the system browser process.
+     */
+    private static void genericChromiumProcessInit(Context context, int maxRendererProcesses,
+            boolean hostIsChrome) {
+        if (sInitialized) {
+            return;
+        }
+        sInitialized = true;
+
+        // Normally Main.java will have already loaded the library asynchronously, we only
+        // need to load it here if we arrived via another flow, e.g. bookmark access & sync setup.
+        LibraryLoader.loadAndInitSync();
+
+        Context appContext = context.getApplicationContext();
+
+        int maxRenderers = normalizeMaxRendererProcesses(appContext, maxRendererProcesses);
+        Log.i(TAG, "Initializing chromium process, renderers=" + maxRenderers +
+                " hostIsChrome=" + hostIsChrome);
+
+        nativeSetCommandLineFlags(maxRenderers, getPlugins(context));
+        ContentMain.initApplicationContext(appContext);
+        ContentMain.start();
+    }
+
+    private static String getPlugins(final Context context) {
+        return "";
+    }
+
+    private static native void nativeSetCommandLineFlags(
+        int maxRenderProcesses, String plugin_descriptor);
+
+    // Is this an official build of Chrome?  Only native code knows
+    // for sure.  Official build knowledge is needed very early in
+    // process startup.
+    private static native boolean nativeIsOfficialBuild();
+}