Added browser_process_main.

content/public/android/java/org/chromium/content/browser/BrowserProcessMain.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.graphics.SurfaceTexture;
+import android.util.Log;
+import android.view.Surface;
+
+import org.chromium.base.CalledByNative;
+
+// NOTE: The un-upstreamed features have been removed from this file, please
+// don't merge this file to the downstream.
+class BrowserProcessMain {
+
+    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.
+    static final int MAX_RENDERERS_AUTOMATIC = -1;
+    // Use single-process mode that runs the renderer on a separate thread in the main application.
+    static final int MAX_RENDERERS_SINGLE_PROCESS = 0;
+    // Cap on the maximum number of renderer processes that can be requested.
+    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().
+     */
+    static void initContentViewProcess(Context context, int maxRendererProcesses) {
+        genericChromiumProcessInit(context, maxRendererProcesses);
+    }
+
+    /**
+     * 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().
+     */
+    static void initChromiumBrowserProcess(Context context, int maxRendererProcesses) {
+        genericChromiumProcessInit(context, maxRendererProcesses);
+    }
+
+    /**
+     * Shared implementation for the initXxx methods.
+     * @param context Context used to obtain the application context
+     * @param maxRendererProcesses See ContentView.enableMultiProcess()
+     */
+    private static void genericChromiumProcessInit(Context context, int maxRendererProcesses) {
+        if (sInitialized) {
+            return;
+        }
+        sInitialized = true;
+
+        // Normally Main.java will have kicked this off asynchronously for Chrome. But
+        // other ContentView apps like tests also need them so we make sure we've
+        // extracted resources here. We can still make it a little async (wait until
+        // the library is loaded).
+        // TODO (michaelbai): Upstream ResourceExtractor.
+        // ResourceExtractor resourceExtractor = ResourceExtractor.get(context);
+        // resourceExtractor.startExtractingResources();
+
+        // 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);
+
+        nativeInitBrowserProcess(appContext, maxRenderers, getPlugins(context));
+    }
+
+    private static String getPlugins(final Context context) {
+        Log.i(TAG, "BrowserProcessMain.getPlugins() is NOT upstreamed.");
+        return "";
+    }
+
+    // Prepare the process for browser/ContentView use. See browser_process_main.{h,cc}.
+    private static native void nativeInitBrowserProcess(Context applicationContext,
+            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();
+}