Really de-flake ChildProcessLauncherTest#testBindServiceFromMultipleProcesses.

content/public/android/javatests/src/org/chromium/content/browser/ChildProcessLauncherTest.java

 // Copyright 2014 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.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.content.ServiceConnection;
 import android.os.Handler;
 import android.os.IBinder;
 import android.os.Looper;
 import android.os.Message;
 import android.os.Messenger;
 import android.os.RemoteException;
 import android.support.test.filters.MediumTest;
 import android.test.InstrumentationTestCase;
 
 import org.chromium.base.BaseSwitches;
 import org.chromium.base.library_loader.LibraryLoader;
 import org.chromium.base.library_loader.LibraryProcessType;
 import org.chromium.base.test.util.CommandLineFlags;
 import org.chromium.base.test.util.Feature;
 import org.chromium.content.browser.test.util.Criteria;
 import org.chromium.content.browser.test.util.CriteriaHelper;
 import org.chromium.content.common.FileDescriptorInfo;
 import org.chromium.content_shell_apk.ChildProcessLauncherTestHelperService;
 
-import java.util.Map;
 import java.util.concurrent.Callable;
 
 /**
  * Instrumentation tests for ChildProcessLauncher.
  */
 public class ChildProcessLauncherTest extends InstrumentationTestCase {
     // Pseudo command line arguments to instruct the child process to wait until being killed.
     // Allowing the process to continue would lead to a crash when attempting to initialize IPC
     // channels that are not being set up in this test.
     private static final String[] sProcessWaitArguments = {
@@ skipping 351 matching lines @@
                 getDefaultChildProcessCreationParams(context.getPackageName()));
 
         CriteriaHelper.pollInstrumentationThread(
                 new Criteria("Failed waiting for instrumentation-bound service") {
                     @Override
                     public boolean isSatisfied() {
                         return conn.getService() != null;
                     }
                 });
 
-        triggerConnectionSetup((ChildProcessConnectionImpl) conn);
+        assertEquals(0, conn.getServiceNumber());
 
-        assertEquals(0, conn.getServiceNumber());
-        assertEquals(-1, conn.getPid());  // PID gets set to -1 if service is already bound.
-
-        final Map<Integer, ChildProcessConnection> serviceMap =
-                ChildProcessLauncher.getServiceMapForTesting();
+        final ChildProcessConnection[] sandboxedConnections =
+                ChildProcessLauncher.getSandboxedConnectionArrayForTesting(
+                        context.getPackageName());
 
         // Wait for the retry to succeed.
         CriteriaHelper.pollInstrumentationThread(
                 new Criteria("Failed waiting for both child process services") {
                     @Override
                     public boolean isSatisfied() {
-                        boolean allChildrenConnected = serviceMap.size() == 2;
-                        for (ChildProcessConnection conn : serviceMap.values()) {
-                            allChildrenConnected &= conn.getService() != null;
+                        boolean allChildrenConnected = true;
+                        for (int i = 0; i < sandboxedConnections.length; ++i) {
+                            ChildProcessConnection conn = sandboxedConnections[i];
+                            if (i <= 1) {
+                                allChildrenConnected &= conn != null && conn.getService() != null;
+                            } else {
+                                allChildrenConnected &= conn == null;

[boliu, 2017/01/26 19:00:35]

is there any reason to check this?

[Robert Sesek, 2017/01/26 19:27:01]

Just to ensure the retry only happens once.

[boliu, 2017/01/26 19:30:28]

You can check that after the poll, this just makes the poll more brittle?

[Robert Sesek, 2017/01/26 19:47:24]

Done.

+                            }
                         }
                         return allChildrenConnected;
                     }
                 });
 
-        assertEquals(2, serviceMap.size());
+        assertTrue(conn == sandboxedConnections[0]);
+        final ChildProcessConnection retryConn = sandboxedConnections[1];
 
-        boolean testedSlot0 = false, testedSlot1 = false;
+        assertFalse(conn == retryConn);
 
-        for (ChildProcessConnection childProcess : serviceMap.values()) {
-            if (childProcess == conn) {
-                assertFalse(testedSlot0);
-                assertEquals(0, childProcess.getServiceNumber());
-                assertEquals(-1, childProcess.getPid());
-                assertFalse(childProcess.getService().bindToCaller());
-                testedSlot0 = true;
-            } else {
-                assertFalse(testedSlot1);
-                assertEquals(1, childProcess.getServiceNumber());
-                assertTrue(childProcess.getPid() > 0);
-                assertTrue(childProcess.getPid() != helperConnPid);
-                assertTrue(childProcess.getService().bindToCaller());
-                testedSlot1 = true;
-            }
-        }
+        assertEquals(0, conn.getServiceNumber());
+        assertEquals(0, conn.getPid());
+        assertFalse(conn.getService().bindToCaller());
 
-        assertTrue(testedSlot0);
-        assertTrue(testedSlot1);
+        assertEquals(1, retryConn.getServiceNumber());
+        assertTrue(retryConn.getPid() > 0);
+        assertTrue(retryConn.getPid() != helperConnPid);
+        assertTrue(retryConn.getService().bindToCaller());
     }
 
     private ChildProcessConnectionImpl startConnection() {
         // Allocate a new connection.
         Context context = getInstrumentation().getTargetContext();
         final ChildProcessConnectionImpl connection =
                 (ChildProcessConnectionImpl) ChildProcessLauncher.allocateBoundConnectionForTesting(
                         context, getDefaultChildProcessCreationParams(context.getPackageName()));
 
         // Wait for the service to connect.
@@ skipping 31 matching lines @@
     private ChildProcessCreationParams getDefaultChildProcessCreationParams(String packageName) {
         return new ChildProcessCreationParams(packageName, false /* isExternalService */,
                 LibraryProcessType.PROCESS_CHILD);
     }
 
     private void triggerConnectionSetup(ChildProcessConnectionImpl connection) {
         ChildProcessLauncher.triggerConnectionSetup(connection, sProcessWaitArguments, 1,
                 new FileDescriptorInfo[0], ChildProcessLauncher.CALLBACK_FOR_RENDERER_PROCESS, 0);
     }
 }