diff --git a/core/fpdfapi/font/cpdf_tounicodemap.cpp b/core/fpdfapi/font/cpdf_tounicodemap.cpp
index 96649e4..26bb35c 100644
--- a/core/fpdfapi/font/cpdf_tounicodemap.cpp
+++ b/core/fpdfapi/font/cpdf_tounicodemap.cpp
@@ -72,7 +72,7 @@
 }
 
 // static
-pdfium::Optional<uint32_t> CPDF_ToUnicodeMap::StringToCode(ByteStringView str) {
+Optional<uint32_t> CPDF_ToUnicodeMap::StringToCode(ByteStringView str) {
   size_t len = str.GetLength();
   if (len <= 2 || str[0] != '<' || str[len - 1] != '>')
     return pdfium::nullopt;
@@ -86,7 +86,7 @@
     if (!code.IsValid())
       return pdfium::nullopt;
   }
-  return pdfium::Optional<uint32_t>(code.ValueOrDie());
+  return Optional<uint32_t>(code.ValueOrDie());
 }
 
 // static
@@ -148,7 +148,7 @@
     if (word.IsEmpty() || word == "endbfchar")
       return;
 
-    pdfium::Optional<uint32_t> code = StringToCode(word);
+    Optional<uint32_t> code = StringToCode(word);
     if (!code.has_value())
       return;
 
@@ -162,12 +162,12 @@
     if (lowcode_str.IsEmpty() || lowcode_str == "endbfrange")
       return;
 
-    pdfium::Optional<uint32_t> lowcode_opt = StringToCode(lowcode_str);
+    Optional<uint32_t> lowcode_opt = StringToCode(lowcode_str);
     if (!lowcode_opt.has_value())
       return;
 
     ByteStringView highcode_str = pParser->GetWord();
-    pdfium::Optional<uint32_t> highcode_opt = StringToCode(highcode_str);
+    Optional<uint32_t> highcode_opt = StringToCode(highcode_str);
     if (!highcode_opt.has_value())
       return;
 
@@ -184,7 +184,7 @@
 
     WideString destcode = StringToWideString(start);
     if (destcode.GetLength() == 1) {
-      pdfium::Optional<uint32_t> value_or_error = StringToCode(start);
+      Optional<uint32_t> value_or_error = StringToCode(start);
       if (!value_or_error.has_value())
         return;
 
diff --git a/core/fpdfapi/font/cpdf_tounicodemap.h b/core/fpdfapi/font/cpdf_tounicodemap.h
index 2872192..5c719dd 100644
--- a/core/fpdfapi/font/cpdf_tounicodemap.h
+++ b/core/fpdfapi/font/cpdf_tounicodemap.h
@@ -28,7 +28,7 @@
   friend class cpdf_tounicodemap_StringToCode_Test;
   friend class cpdf_tounicodemap_StringToWideString_Test;
 
-  static pdfium::Optional<uint32_t> StringToCode(ByteStringView str);
+  static Optional<uint32_t> StringToCode(ByteStringView str);
   static WideString StringToWideString(ByteStringView str);
 
   void Load(const CPDF_Stream* pStream);
diff --git a/core/fxge/win32/cgdi_device_driver.h b/core/fxge/win32/cgdi_device_driver.h
index b672532..de16a15 100644
--- a/core/fxge/win32/cgdi_device_driver.h
+++ b/core/fxge/win32/cgdi_device_driver.h
@@ -72,7 +72,7 @@
   int m_nBitsPerPixel;
   const DeviceType m_DeviceType;
   int m_RenderCaps;
-  pdfium::Optional<FX_RECT> m_BaseClipBox;
+  Optional<FX_RECT> m_BaseClipBox;
 };
 
 #endif  // CORE_FXGE_WIN32_CGDI_DEVICE_DRIVER_H_