Reset Default Font on exit from PlatformFontLinuxTest.

ui/gfx/platform_font_linux_unittest.cc

 // Copyright (c) 2012 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/gfx/platform_font_linux.h"
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ skipping 52 matching lines @@
  public:
   PlatformFontLinuxTest() {
     SetUpFontconfig();
     original_font_delegate_ = LinuxFontDelegate::instance();
     LinuxFontDelegate::SetInstance(&test_font_delegate_);
   }
 
   ~PlatformFontLinuxTest() override {
     LinuxFontDelegate::SetInstance(
         const_cast<LinuxFontDelegate*>(original_font_delegate_));
+    PlatformFontLinux::ReloadDefaultFont();
     TearDownFontconfig();
   }
 
  protected:
   TestFontDelegate test_font_delegate_;
 
  private:
   // Originally-registered delegate.
   const LinuxFontDelegate* original_font_delegate_;
 
@@ skipping 39 matching lines @@
 #endif
   PlatformFontLinux::ReloadDefaultFont();
   scoped_refptr<gfx::PlatformFontLinux> font2(new gfx::PlatformFontLinux());
   EXPECT_EQ("Times New Roman", font2->GetFontName());
   EXPECT_EQ(15, font2->GetFontSize());
   EXPECT_NE(font2->GetStyle() & Font::ITALIC, 0);
   EXPECT_EQ(gfx::Font::Weight::BOLD, font2->GetWeight());
 }
 
 }  // namespace gfx