Use list instead of pair to represent the set of displays.

ash/display/display_util_unittest.cc

 // Copyright 2014 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 "ash/display/display_util.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "ash/test/display_manager_test_api.h"
@@ skipping 74 matching lines @@
     AshWindowTreeHost* host1 =
         GetRootWindowController(root_windows[1])->ash_host();
     gfx::Rect rect0 = GetNativeEdgeBounds(host0, gfx::Rect(499, 10, 1, 300));
     gfx::Rect rect1 = GetNativeEdgeBounds(host1, gfx::Rect(500, 10, 1, 300));
     EXPECT_EQ("10,99 1x300", rect0.ToString());
     EXPECT_EQ("600,20 1x300", rect1.ToString());
   }
 }
 
 TEST_F(DisplayUtilTest, CreateDisplayIdPair) {
-  DisplayIdPair pair = CreateDisplayIdPair(10, 1);
-  EXPECT_EQ(1, pair.first);
-  EXPECT_EQ(10, pair.second);
-  pair = CreateDisplayIdPair(10, 100);
-  EXPECT_EQ(10, pair.first);
-  EXPECT_EQ(100, pair.second);
+  DisplayIdList list = CreateDisplayIdList(10, 1);
+  EXPECT_EQ(1, list[0]);
+  EXPECT_EQ(10, list[1]);
+  list = CreateDisplayIdList(10, 100);
+  EXPECT_EQ(10, list[0]);
+  EXPECT_EQ(100, list[1]);
   {
     test::ScopedSetInternalDisplayId set_internal(100);
-    pair = CreateDisplayIdPair(10, 100);
-    EXPECT_EQ(100, pair.first);
-    EXPECT_EQ(10, pair.second);
+    list = CreateDisplayIdList(10, 100);
+    EXPECT_EQ(100, list[0]);
+    EXPECT_EQ(10, list[1]);
 
-    pair = CreateDisplayIdPair(100, 10);
-    EXPECT_EQ(100, pair.first);
-    EXPECT_EQ(10, pair.second);
+    list = CreateDisplayIdList(100, 10);
+    EXPECT_EQ(100, list[0]);
+    EXPECT_EQ(10, list[1]);
   }
 
   {
     test::ScopedSetInternalDisplayId set_internal(10);
-    pair = CreateDisplayIdPair(10, 100);
-    EXPECT_EQ(10, pair.first);
-    EXPECT_EQ(100, pair.second);
+    list = CreateDisplayIdList(10, 100);
+    EXPECT_EQ(10, list[0]);
+    EXPECT_EQ(100, list[1]);
 
-    pair = CreateDisplayIdPair(100, 10);
-    EXPECT_EQ(10, pair.first);
-    EXPECT_EQ(100, pair.second);
+    list = CreateDisplayIdList(100, 10);
+    EXPECT_EQ(10, list[0]);
+    EXPECT_EQ(100, list[1]);
   }
 }
 
 }  // namespace