Split cocoa_event_utils in two parts.

ui/base/cocoa/cocoa_base_utils_unittest.mm

Index: ui/base/cocoa/cocoa_base_utils_unittest.mm
diff --git a/ui/base/cocoa/cocoa_base_utils_unittest.mm b/ui/base/cocoa/cocoa_base_utils_unittest.mm
new file mode 100644
index 0000000000000000000000000000000000000000..fff729079f52263c00567813879b123ad6a8bdad
--- /dev/null
+++ b/ui/base/cocoa/cocoa_base_utils_unittest.mm
@@ -0,0 +1,68 @@
+// Copyright 2013 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.
+
+#include "ui/base/cocoa/cocoa_base_utils.h"
+
+#import <objc/objc-class.h>
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/platform_test.h"
+#include "ui/events/event_constants.h"
+#import "ui/events/test/cocoa_test_event_utils.h"
+#import "ui/gfx/test/ui_cocoa_test_helper.h"
+
+// We provide a donor class with a specially modified |modifierFlags|
+// implementation that we swap with NSEvent's. This is because we can't create a
+// NSEvent that represents a middle click with modifiers.
+@interface TestEvent : NSObject
+@end
+@implementation TestEvent
+- (NSUInteger)modifierFlags { return NSShiftKeyMask; }
+@end
+
+namespace ui {
+
+namespace {
+
+class CocoaBaseUtilsTest : public CocoaTest {
+};
+
+TEST_F(CocoaBaseUtilsTest, WindowOpenDispositionFromNSEvent) {
+  // Left Click = same tab.
+  NSEvent* me = cocoa_test_event_utils::MouseEventWithType(NSLeftMouseUp, 0);
+  EXPECT_EQ(CURRENT_TAB, WindowOpenDispositionFromNSEvent(me));
+
+  // Middle Click = new background tab.
+  me = cocoa_test_event_utils::MouseEventWithType(NSOtherMouseUp, 0);
+  EXPECT_EQ(NEW_BACKGROUND_TAB, WindowOpenDispositionFromNSEvent(me));
+
+  // Shift+Middle Click = new foreground tab.
+  {
+    ScopedClassSwizzler swizzler([NSEvent class], [TestEvent class],
+                                 @selector(modifierFlags));
+    me = cocoa_test_event_utils::MouseEventWithType(NSOtherMouseUp,
+                                                    NSShiftKeyMask);
+    EXPECT_EQ(NEW_FOREGROUND_TAB, WindowOpenDispositionFromNSEvent(me));
+  }
+
+  // Cmd+Left Click = new background tab.
+  me = cocoa_test_event_utils::MouseEventWithType(NSLeftMouseUp,
+                                                  NSCommandKeyMask);
+  EXPECT_EQ(NEW_BACKGROUND_TAB, WindowOpenDispositionFromNSEvent(me));
+
+  // Cmd+Shift+Left Click = new foreground tab.
+  me = cocoa_test_event_utils::MouseEventWithType(NSLeftMouseUp,
+                                              NSCommandKeyMask |
+                                              NSShiftKeyMask);
+  EXPECT_EQ(NEW_FOREGROUND_TAB, WindowOpenDispositionFromNSEvent(me));
+
+  // Shift+Left Click = new window
+  me = cocoa_test_event_utils::MouseEventWithType(NSLeftMouseUp,
+                                                  NSShiftKeyMask);
+  EXPECT_EQ(NEW_WINDOW, WindowOpenDispositionFromNSEvent(me));
+}
+
+}  // namespace
+
+}  // namespace ui