DO NOT SUBMIT: add main dex list check to classloader.

base/android/java/src/org/chromium/base/multidex/ChromiumClassLoader.java

Index: base/android/java/src/org/chromium/base/multidex/ChromiumClassLoader.java
diff --git a/base/android/java/src/org/chromium/base/multidex/ChromiumClassLoader.java b/base/android/java/src/org/chromium/base/multidex/ChromiumClassLoader.java
new file mode 100644
index 0000000000000000000000000000000000000000..49bfb5c594daead4be786585c4c97edcd7f5f6f2
--- /dev/null
+++ b/base/android/java/src/org/chromium/base/multidex/ChromiumClassLoader.java
@@ -0,0 +1,120 @@
+// Copyright 2017 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.base.multidex;
+
+import static org.chromium.base.Reflect.getField;
+
+import android.annotation.TargetApi;
+import android.content.Context;
+import android.content.ContextWrapper;
+import android.os.Build;
+
+import dalvik.system.PathClassLoader;
+
+import org.chromium.base.BuildConfig;
+import org.chromium.base.ContextUtils;
+import org.chromium.base.FileUtils;
+import org.chromium.base.Log;
+import org.chromium.base.Reflect;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.Collections;
+import java.util.HashSet;
+
+public class ChromiumClassLoader extends PathClassLoader {
+    private static final String TAG = "ChromiumClassLoader";
+    private static final String SEPERATOR = ",";
+    private static final String MAIN_DEX_LIST_FILE = "classes.dex.zip_java_list.csv";
+
+    private ClassLoader mClassLoaderDelegate;
+    private HashSet<String> mMainDexClasses;
+
+    @TargetApi(Build.VERSION_CODES.N)
+    private static ChromiumClassLoader create(Context context) {
+        try {
+            Object packageInfo = getField(getContextImpl(context), "mPackageInfo");
+            ClassLoader parent = (ClassLoader) Reflect.getField(packageInfo, "mClassLoader");
+            return new ChromiumClassLoader(context.getPackageCodePath(), parent);
+        } catch (Exception e) {
+            Log.d(TAG, "Encountered exception: " + e.getMessage());
+        }
+        return null;
+    }
+
+    private ChromiumClassLoader(String dexPath, ClassLoader parent) {
+        super(dexPath, parent);
+        mClassLoaderDelegate = parent;
+    }
+
+    @Override
+    public Class<?> loadClass(String name) throws ClassNotFoundException {
+        assert mMainDexClasses != null;
+        Log.d(TAG, "Loading class: " + name);
+        if ((name.startsWith("com.google") || name.startsWith("org.chromium"))
+                && !mMainDexClasses.contains(name)) {
+            Log.wtf(TAG, "ERROR loading class: " + name);
+            throw new AssertionError();
+        }
+        return mClassLoaderDelegate.loadClass(name);
+    }
+
+    private void buildMainDexList() {
+        String file = FileUtils.extractAsset(MAIN_DEX_LIST_FILE);
+        mMainDexClasses = new HashSet<String>();
+        Collections.addAll(mMainDexClasses, file.split(SEPERATOR));
+    }
+
+    /**
+     *
+     * @param context
+     * @param cl
+     */
+    private static void installClassLoader(Context context, ClassLoader cl) {
+        try {
+            Object packageInfo = getField(getContextImpl(context), "mPackageInfo");
+            Reflect.setField(packageInfo, "mClassLoader", cl);
+            Thread.currentThread().setContextClassLoader(cl);
+
+        } catch (Exception e) {
+            Log.d("ChromiumClassLoader", "Encountered exception: " + e.getMessage());
+        }
+    }
+
+    private static Context getContextImpl(Context context) {
+        while (context instanceof ContextWrapper) {
+            ContextWrapper wrapper = (ContextWrapper) context;
+            if (wrapper.getBaseContext() == null || wrapper.getBaseContext() == context) {
+                break;
+            }
+            context = wrapper.getBaseContext();
+        }
+        return context;
+    }
+
+    private static boolean isIsolatedProcess() {
+        try {
+            Method isIsolatedMethod = android.os.Process.class.getMethod("isIsolated");
+            Object retVal = isIsolatedMethod.invoke(null);
+            return retVal != null && retVal instanceof Boolean && ((Boolean) retVal);
+        } catch (NoSuchMethodException e) {
+            e.printStackTrace();
+        } catch (IllegalAccessException e) {
+            e.printStackTrace();
+        } catch (InvocationTargetException e) {
+            e.printStackTrace();
+        }
+        return false;
+    }
+
+    public static void initDebugClassLoader() {
+        if (!BuildConfig.isOfficialBuild() && isIsolatedProcess()) {
+            Context appContext = ContextUtils.getApplicationContext();
+            ChromiumClassLoader cl = create(appContext);
+            cl.buildMainDexList();
+            installClassLoader(appContext, cl);
+        }
+    }
+}