Enable hidpi on Linux, refactor a bit on Windows to share

ui/base/test/run_all_unittests.cc

Index: ui/base/test/run_all_unittests.cc
diff --git a/ui/base/test/run_all_unittests.cc b/ui/base/test/run_all_unittests.cc
index cb2067a49c2ab1afc98927ec3f319051dd4e6a1e..2c4f6a6e58e426d7e815af4df404f6838d916c44 100644
--- a/ui/base/test/run_all_unittests.cc
+++ b/ui/base/test/run_all_unittests.cc
@@ -10,6 +10,7 @@
 #include "build/build_config.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_paths.h"
+#include "ui/gfx/dpi.h"
 
 #if defined(OS_ANDROID)
 #include "base/android/jni_android.h"
@@ -22,10 +23,6 @@
 #include "base/test/mock_chrome_application_mac.h"
 #endif
 
-#if defined(OS_WIN)
-#include "ui/gfx/win/dpi.h"
-#endif
-
 namespace {
 
 class UIBaseTestSuite : public base::TestSuite {
@@ -47,7 +44,7 @@ UIBaseTestSuite::UIBaseTestSuite(int argc, char** argv)
 void UIBaseTestSuite::Initialize() {
   base::TestSuite::Initialize();
 
-#if defined(OS_WIN)
+#if defined(OS_WIN) || (defined(OS_LINUX) && !defined(OS_CHROMEOS))
   gfx::ForceHighDPISupportForTesting(1.0);
 #endif