Make sure that NSApplication subclasses are correctly instantiated.

If NSApp is used prior to instantiation of the NSApplication subclass, then the
subclass will never be instantiated.

This CL adds a CHECK to confirm that the subclass is correctly instantiated.

This CL found several tests which were unnecessarily instantiating a UI Message
Loop during the constructor of the gtest subclass, which ends up calling NSApp
prior to NSApplication subclass instantiation.


Change-Id: Ie1d1a2b498623d29578848a18938dc03521940ef
Reviewed-on: https://chromium-review.googlesource.com/1240515
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Avi Drissman <avi@chromium.org>
Reviewed-by: Sami Kyöstilä <skyostil@chromium.org>
Reviewed-by: Sebastien Seguin-Gagnon <sebsg@chromium.org>
Commit-Queue: Erik Chen <erikchen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#593913}

base/test/mock_chrome_application_mac.mm

@@ -39,6 +39,11 @@ namespace mock_cr_app {
 
 void RegisterMockCrApp() {
   [MockCrApp sharedApplication];
+
+  // If there was an invocation to NSApp prior to this method, then the NSApp
+  // will not be a MockCrApp, but will instead be an NSApplication.
+  // This is undesirable and we must enforce that this doesn't happen.
+  CHECK([NSApp isKindOfClass:[MockCrApp class]]);
 }
 
 }  // namespace mock_cr_app

chrome/browser/chrome_browser_application_mac.mm

@@ -28,6 +28,11 @@ namespace chrome_browser_application_mac {
 
 void RegisterBrowserCrApp() {
   [BrowserCrApplication sharedApplication];
+
+  // If there was an invocation to NSApp prior to this method, then the NSApp
+  // will not be a BrowserCrApplication, but will instead be an NSApplication.
+  // This is undesirable and we must enforce that this doesn't happen.
+  CHECK([NSApp isKindOfClass:[BrowserCrApplication class]]);
 };
 
 void Terminate() {

components/autofill/content/browser/risk/fingerprint_browsertest.cc

@@ -199,9 +199,6 @@ class AutofillRiskFingerprintTest : public content::ContentBrowserTest {
   const gfx::Rect unavailable_screen_bounds_;
 
   std::unique_ptr<device::ScopedGeolocationOverrider> geolocation_overrider_;
-
-  // A message loop to block on the asynchronous loading of the fingerprint.
-  base::MessageLoopForUI message_loop_;
 };
 
 // Test that getting a fingerprint works on some basic level.

content/browser/renderer_host/input/mouse_latency_browsertest.cc

@@ -151,7 +151,7 @@ class TracingRenderWidgetHostFactory : public RenderWidgetHostFactory {
 
 class MouseLatencyBrowserTest : public ContentBrowserTest {
  public:
-  MouseLatencyBrowserTest() : loop_(base::MessageLoop::TYPE_UI) {}
+  MouseLatencyBrowserTest() {}
   ~MouseLatencyBrowserTest() override {}
 
   RenderWidgetHostImpl* GetWidgetHost() {
@@ -306,7 +306,6 @@ class MouseLatencyBrowserTest : public ContentBrowserTest {
   }
 
  private:
-  base::MessageLoop loop_;
   std::unique_ptr<base::RunLoop> runner_;
   base::Value trace_data_;
   TracingRenderWidgetHostFactory widget_factory_;

content/browser/renderer_host/input/scroll_latency_browsertest.cc

@@ -62,7 +62,7 @@ namespace content {
 
 class ScrollLatencyBrowserTest : public ContentBrowserTest {
  public:
-  ScrollLatencyBrowserTest() : loop_(base::MessageLoop::TYPE_UI) {}
+  ScrollLatencyBrowserTest() {}
   ~ScrollLatencyBrowserTest() override {}
 
   RenderWidgetHostImpl* GetWidgetHost() {
@@ -140,7 +140,6 @@ class ScrollLatencyBrowserTest : public ContentBrowserTest {
 
  private:
   base::HistogramTester histogram_tester_;
-  base::MessageLoop loop_;
   std::unique_ptr<MainThreadFrameObserver> frame_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(ScrollLatencyBrowserTest);

content/shell/app/shell_main_delegate_mac.mm

@@ -62,6 +62,11 @@ void OverrideBundleID() {
 void RegisterShellCrApp() {
   // Force the NSApplication subclass to be used.
   [ShellCrApplication sharedApplication];
+
+  // If there was an invocation to NSApp prior to this method, then the NSApp
+  // will not be a ShellCrApplication, but will instead be an NSApplication.
+  // This is undesirable and we must enforce that this doesn't happen.
+  CHECK([NSApp isKindOfClass:[ShellCrApplication class]]);
 }
 
 }  // namespace content

headless/lib/headless_content_main_delegate_mac.mm

@@ -11,6 +11,12 @@ namespace headless {
 void HeadlessContentMainDelegate::PreCreateMainMessageLoop() {
   // Force the NSApplication subclass to be used.
   [HeadlessShellCrApplication sharedApplication];
+
+  // If there was an invocation to NSApp prior to this method, then the NSApp
+  // will not be a HeadlessShellCrApplication, but will instead be an
+  // NSApplication. This is undesirable and we must enforce that this doesn't
+  // happen.
+  CHECK([NSApp isKindOfClass:[HeadlessShellCrApplication class]]);
 }
 
 }  // namespace headless