Keep browser process alive while there are platform apps with background pages running.

chrome/browser/extensions/api/media_galleries_private/media_galleries_private_apitest.cc

Index: chrome/browser/extensions/api/media_galleries_private/media_galleries_private_apitest.cc
diff --git a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_apitest.cc b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_apitest.cc
index 05dffbe25b09047636c5e52be05867c4dcecf1e2..51ccbd2ad9740605b76b7ddc0ff61574f976d831 100644
--- a/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_apitest.cc
+++ b/chrome/browser/extensions/api/media_galleries_private/media_galleries_private_apitest.cc
@@ -80,20 +80,27 @@ class MediaGalleriesPrivateApiTest : public ExtensionApiTest {
     EXPECT_TRUE(listener.WaitUntilSatisfied());
   }
 
-  void AttachDetach() {
-    Attach();
-    Detach();
-  }
-
-  void Attach() {
+  void Attach(bool listening) {
+    const std::string expect_attach_msg =
+        base::StringPrintf("%s,%s", kAttachTestOk, kDeviceName);
+    ExtensionTestMessageListener attach_finished_listener(
+        expect_attach_msg,
+        false  /* no reply */);
     base::SystemMonitor::Get()->ProcessRemovableStorageAttached(
         device_id_, ASCIIToUTF16(kDeviceName), kDevicePath);
     WaitForDeviceEvents();
+    if (listening)
+      EXPECT_TRUE(attach_finished_listener.WaitUntilSatisfied());
   }
 
-  void Detach() {
+  void Detach(bool listening) {
+    ExtensionTestMessageListener detach_finished_listener(
+        kDetachTestOk,
+        false  /* no reply */);
     base::SystemMonitor::Get()->ProcessRemovableStorageDetached(device_id_);
     WaitForDeviceEvents();
+    if (listening)
+      EXPECT_TRUE(detach_finished_listener.WaitUntilSatisfied());
   }
 
  private:
@@ -119,49 +126,41 @@ IN_PROC_BROWSER_TEST_F(MediaGalleriesPrivateApiTest, DeviceAttachDetachEvents) {
   ASSERT_TRUE(host);
 
   // No listeners, attach and detach a couple times.
-  AttachDetach();
-  AttachDetach();
+  Attach(false);
+  Detach(false);
+  Attach(false);
+  Detach(false);
 
   // Add attach listener.
   ChangeListener(host, kAddAttachListenerCmd, kAddAttachListenerOk);
 
   // Attach / detach
-  const std::string expect_attach_msg =
-      base::StringPrintf("%s,%s", kAttachTestOk, kDeviceName);
-  ExtensionTestMessageListener attach_finished_listener(expect_attach_msg,
-                                                        false  /* no reply */);
-  Attach();
-  EXPECT_TRUE(attach_finished_listener.WaitUntilSatisfied());
-  Detach();
+  Attach(true);
+  Detach(false);
 
   // Attach / detach
-  Attach();
-  EXPECT_TRUE(attach_finished_listener.WaitUntilSatisfied());
-  // Detach
-  Detach();
+  Attach(true);
+  Detach(false);
 
   // Remove attach listener.
   ChangeListener(host, kRemoveAttachListenerCmd, kRemoveAttachListenerOk);
 
   // No listeners, attach and detach a couple times.
-  AttachDetach();
-  AttachDetach();
+  Attach(false);
+  Detach(false);
+  Attach(false);
+  Detach(false);
 
   // Add detach listener.
   ChangeListener(host, kAddDummyDetachListenerCmd, kAddDummyDetachListenerOk);
 
   // Attach / detach
-  Attach();
-
-  ExtensionTestMessageListener detach_finished_listener(kDetachTestOk,
-                                                        false  /* no reply */);
-  Detach();
-  EXPECT_TRUE(detach_finished_listener.WaitUntilSatisfied());
+  Attach(false);
+  Detach(true);
 
   // Attach / detach
-  Attach();
-  Detach();
-  EXPECT_TRUE(detach_finished_listener.WaitUntilSatisfied());
+  Attach(false);
+  Detach(true);
 
   // Switch ok dummy detach listener for the regular one.
   ChangeListener(host, kRemoveDummyDetachListenerCmd,
@@ -171,13 +170,10 @@ IN_PROC_BROWSER_TEST_F(MediaGalleriesPrivateApiTest, DeviceAttachDetachEvents) {
   // Add attach listener.
   ChangeListener(host, kAddAttachListenerCmd, kAddAttachListenerOk);
 
-  Attach();
-  EXPECT_TRUE(attach_finished_listener.WaitUntilSatisfied());
-  Detach();
-  EXPECT_TRUE(detach_finished_listener.WaitUntilSatisfied());
+  Attach(true);
+  Detach(true);
 
-  Attach();
-  EXPECT_TRUE(attach_finished_listener.WaitUntilSatisfied());
-  Detach();
-  EXPECT_TRUE(detach_finished_listener.WaitUntilSatisfied());
+  Attach(true);
+  Detach(true);
+  CloseShellWindowsAndWaitForAppToExit();
 }