Hookup device dpi for ChromeOS

chrome/browser/extensions/display_info_provider_chromeos_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 "extensions/browser/api/system_display/display_info_provider.h"
 
 #include "ash/ash_switches.h"
 #include "ash/content/display/screen_orientation_controller_chromeos.h"
 #include "ash/display/display_manager.h"
 #include "ash/display/window_tree_host_manager.h"
@@ skipping 147 matching lines @@
 
   result = DisplayInfoProvider::Get()->GetAllDisplaysInfo();
 
   ASSERT_EQ(1u, result.size());
 
   EXPECT_EQ(base::Int64ToString(display_id), result[0]->id);
   EXPECT_EQ("0,0 500x600", SystemInfoDisplayBoundsToString(result[0]->bounds));
   EXPECT_EQ(0, result[0]->rotation);
 }
 
-TEST_F(DisplayInfoProviderChromeosTest, GetHiDPI) {
+TEST_F(DisplayInfoProviderChromeosTest, GetDPI) {
   UpdateDisplay("500x600,400x520*2");
   DisplayInfo result;
   result = DisplayInfoProvider::Get()->GetAllDisplaysInfo();
 
   ASSERT_EQ(2u, result.size());
 
   EXPECT_EQ("0,0 500x600", SystemInfoDisplayBoundsToString(result[0]->bounds));
   EXPECT_EQ(96, result[0]->dpi_x);
   EXPECT_EQ(96, result[0]->dpi_y);
 
   EXPECT_EQ("500,0 200x260",
             SystemInfoDisplayBoundsToString(result[1]->bounds));
-  EXPECT_EQ(2 * 96, result[1]->dpi_x);
-  EXPECT_EQ(2 * 96, result[1]->dpi_y);
+  // DPI should be 96 (native dpi) * 200 (display) / 400 (native) when ui scale
+  // is 2.
+  EXPECT_EQ(96 / 2, result[1]->dpi_x);
+  EXPECT_EQ(96 / 2, result[1]->dpi_y);
 
   GetWindowTreeHostManager()->SwapPrimaryDisplay();
 
   result = DisplayInfoProvider::Get()->GetAllDisplaysInfo();
 
   ASSERT_EQ(2u, result.size());
 
   EXPECT_EQ("-500,0 500x600",
             SystemInfoDisplayBoundsToString(result[0]->bounds));
   EXPECT_EQ(96, result[0]->dpi_x);
   EXPECT_EQ(96, result[0]->dpi_y);
 
   EXPECT_EQ("0,0 200x260", SystemInfoDisplayBoundsToString(result[1]->bounds));
-  EXPECT_EQ(2 * 96, result[1]->dpi_x);
-  EXPECT_EQ(2 * 96, result[1]->dpi_y);
+  EXPECT_EQ(96 / 2, result[1]->dpi_x);
+  EXPECT_EQ(96 / 2, result[1]->dpi_y);
 }
 
 TEST_F(DisplayInfoProviderChromeosTest, GetVisibleArea) {
   UpdateDisplay("640x720*2/o, 400x520/o");
   DisplayInfo result;
   result = DisplayInfoProvider::Get()->GetAllDisplaysInfo();
 
   ASSERT_EQ(2u, result.size());
 
   int64 display_id;
@@ skipping 750 matching lines @@
   std::string error;
   CallSetDisplayUnitInfo(
       base::Int64ToString(internal_display_id), info, &success, &error);
 
   ASSERT_FALSE(success);
   EXPECT_EQ("Overscan changes not allowed for the internal monitor.", error);
 }
 
 }  // namespace
 }  // namespace extensions