Get a minimal unit_tests target building and running for iOS

chrome/test/base/testing_browser_process.h

Index: chrome/test/base/testing_browser_process.h
diff --git a/chrome/test/base/testing_browser_process.h b/chrome/test/base/testing_browser_process.h
index 6395fed97b714b2b2ed11e5d9a0382cda3cda24c..b2138d0afa6fc7910f79a07f2f78aa5de6ceb2fe 100644
--- a/chrome/test/base/testing_browser_process.h
+++ b/chrome/test/base/testing_browser_process.h
@@ -116,6 +116,8 @@ class TestingBrowserProcess : public BrowserProcess {
 
   // Weak pointer.
   PrefService* local_state_;
+  // TODO(ios): Add back members as more code is compiled.
+#if !defined(OS_IOS)
 #if defined(ENABLE_CONFIGURATION_POLICY)
   scoped_ptr<policy::BrowserPolicyConnector> browser_policy_connector_;
 #else
@@ -128,9 +130,13 @@ class TestingBrowserProcess : public BrowserProcess {
       print_preview_tab_controller_;
   scoped_ptr<prerender::PrerenderTracker> prerender_tracker_;
   scoped_ptr<RenderWidgetSnapshotTaker> render_widget_snapshot_taker_;
+#endif  // !defined(OS_IOS)
   IOThread* io_thread_;
+  // TODO(ios): Add back members as more code is compiled.
+#if !defined(OS_IOS)
   scoped_refptr<SafeBrowsingService> sb_service_;
   scoped_ptr<BookmarkPromptController> bookmark_prompt_controller_;
+#endif  // !defined(OS_IOS)
   net::URLRequestContextGetter* system_request_context_;
 
   DISALLOW_COPY_AND_ASSIGN(TestingBrowserProcess);