ui: add --disable-modal-animations for Mac

This switch is similar to the existing --wm-window-animations-disabled switch,
which is Aura/Ash-specific, but more tightly scoped and available only on Mac.
This allows tests to disable closure animations for modal dialogs, which take
a few hundred ms each and introduce test flake.

Bug: 817408
Change-Id: Id6d2703d58b25f0efa34085d34f467ad1bf5a912
Reviewed-on: https://chromium-review.googlesource.com/973463
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#544884}

chrome/browser/ui/views/passwords/password_dialog_view_browsertest.cc

@@ -8,6 +8,7 @@
 #include "base/run_loop.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
+#include "build/build_config.h"
 #include "chrome/browser/password_manager/chrome_password_manager_client.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/browser.h"
@@ -26,6 +27,7 @@
 #include "net/test/embedded_test_server/http_request.h"
 #include "net/test/embedded_test_server/http_response.h"
 #include "testing/gmock/include/gmock/gmock.h"
+#include "ui/base/ui_base_switches.h"
 #include "ui/views/test/widget_test.h"
 #include "ui/views/widget/widget.h"
 
@@ -134,6 +136,13 @@ class PasswordDialogViewTest : public DialogBrowserTest {
 };
 
 void PasswordDialogViewTest::SetUpOnMainThread() {
+#if defined(OS_MACOSX)
+  // On non-Mac platforms, animations are globally disabled during tests; on
+  // Mac they are generally not, but these tests are dramatically slower and
+  // flakier with animations.
+  base::CommandLine::ForCurrentProcess()->AppendSwitch(
+      switches::kDisableModalAnimations);
+#endif
   SetupTabWithTestController(browser());
 }
 

ui/base/ui_base_switches.cc

@@ -14,6 +14,9 @@ const char kDisableAVFoundationOverlays[] = "disable-avfoundation-overlays";
 // based overlay display path.
 const char kDisableMacOverlays[] = "disable-mac-overlays";
 
+// Disable animations for showing and hiding modal dialogs.
+const char kDisableModalAnimations[] = "disable-modal-animations";
+
 // Disable use of cross-process CALayers to display content directly from the
 // GPU process on Mac.
 const char kDisableRemoteCoreAnimation[] = "disable-remote-core-animation";

ui/base/ui_base_switches.h

@@ -15,6 +15,7 @@ namespace switches {
 #if defined(OS_MACOSX) && !defined(OS_IOS)
 UI_BASE_EXPORT extern const char kDisableAVFoundationOverlays[];
 UI_BASE_EXPORT extern const char kDisableMacOverlays[];
+UI_BASE_EXPORT extern const char kDisableModalAnimations[];
 UI_BASE_EXPORT extern const char kDisableRemoteCoreAnimation[];
 UI_BASE_EXPORT extern const char kShowMacOverlayBorders[];
 #endif

ui/views/widget/native_widget_mac.mm

@@ -8,6 +8,7 @@
 
 #include <utility>
 
+#include "base/command_line.h"
 #import "base/mac/bind_objc_block.h"
 #include "base/mac/foundation_util.h"
 #include "base/mac/scoped_nsobject.h"
@@ -16,6 +17,7 @@
 #include "components/crash/core/common/crash_key.h"
 #import "ui/base/cocoa/constrained_window/constrained_window_animation.h"
 #import "ui/base/cocoa/window_size_constants.h"
+#include "ui/base/ui_base_switches.h"
 #include "ui/gfx/font_list.h"
 #import "ui/gfx/mac/coordinate_conversion.h"
 #import "ui/gfx/mac/nswindow_frame_controls.h"
@@ -46,6 +48,11 @@
 namespace views {
 namespace {
 
+bool AreModalAnimationsEnabled() {
+  return !base::CommandLine::ForCurrentProcess()->HasSwitch(
+      switches::kDisableModalAnimations);
+}
+
 NSInteger StyleMaskForParams(const Widget::InitParams& params) {
   // If the Widget is modal, it will be displayed as a sheet. This works best if
   // it has NSTitledWindowMask. For example, with NSBorderlessWindowMask, the
@@ -365,7 +372,8 @@ void NativeWidgetMac::Close() {
   }
 
   // For other modal types, animate the close.
-  if (bridge_->animate() && delegate_->IsModal()) {
+  if (bridge_->animate() && AreModalAnimationsEnabled() &&
+      delegate_->IsModal()) {
     [ViewsNSWindowCloseAnimator closeWindowWithAnimation:window];
     return;
   }